Spin

STAR Spin Working Group 

 

 

Unraveling the quark and gluon substructure of nucleons and nuclei is one of the major goals in nuclear physics today. A great deal has been learned about the partonic structure of the nucleon at leading twist and with collinear factorization, but much is still unknown. Furthermore, new avenues have been opened during the past decade to explore the nucleon structure beyond leading twist and collinear factorization. The ability to collide polarized beams at RHIC provides unique information regarding these issues.

                                 - STAR Decadal Plan (2010)

Spin PWG

Spin Physics Working Group pages

This is a feed of Drupal items targeting the "Spin" Audience.

Spin/Cold-QCD Older Physics Analysis

Detailed information about physics analyses in the spin pwg

Link to STAR spin task force (2008)

(page started in March of 2008)

2006 EEMC Neutral Pion Cross Section and A_LL

The 2006 EEMC cross section, ALL, and AN were published in Physical Review D 89, 012001 (2014). Please, see the paper home page for links to detailed information.

Relevant Links

2006 Gamma + Jet

Relevant Links

Intent to Publish 2006 Gamma + Jet Cross Section

Title

Gamma-jet cross sections for forward gammas in proton-proton collisions at root(s) = 200 GeV/c

Principal Authors (alphabetical order)

Keith Krueger (ANL), Hal Spinka (ANL), Dave Underwood (ANL)

Intended Journal

Physical Review D

Abstract

A measurement is presented of the cross section vs. transverse momentum (pT) for gamma + jet production in proton-proton collisions. The data were measured in the STAR detector at RHIC at √s = 200 GeV/c. The jet was detected at central pseudorapidity (|η| < 0.8) and the γ at intermediate pseudorapidity (1.2 < η < 2.0). These regions were chosen to access lower x of the gluon relative to a central-pseudorapidity-only measurement, and also because a large partonic spin asymmetry, All, in the parton cm is selected. The technique of finding single γ’s in the background of photons from π0 decay is based on a standard chi-squared method for the shower shape in the shower maximum detector of an electromagnetic calorimeter.

Outline

  • Introduction
    • Refs. to earlier measurements and theory predictions
    • Connection to gluon distribution
  • Hardware
    • RHIC general (Refs.)
    • STAR general (Refs.)
    • TPC and BEMC for jets (Refs.)
    • EEMC and ESMD for gamma
    • trigger
    • luminosity
  • Analysis
    • Jets (Refs.)
    • Gammas with chi-squared (Ref.)
    • Efficiency / RooUnfold
    • Other Corrections?
    • Systematics
    • Table of results with errors
  • Results
    • Comparison to JETPHOX (Refs.)
    • Comparison to pi0’s?
  • Summary / Conclusions

Presentations to the Spin PWG (April 23)

2009 Lambda D_LL @ 200 GeV



Presentations: 



Run QA by Qinghua Xu (SDU) 
 

1) Preliminary results

Preliminary released on SPIN 2012 and DNP 2012. 

Presentation @ SPIN 2012 by Jian Deng (SDU)
Presentation @ DNP 2012 by Ramon Cendejas (UCLA)

2) Lambda reconstruction

 

1. Cuts setup:
lam_pt dac2 dcaV0 dca_p dca_pi nsigma dlength cosrp jet_det_eta jet_Rt jet_dr
2,3 <0.7 <1.2 >0.2 (0.4,30) <3 (3,130) >0.98 (-0.7,0.7) (0.01,0.94) <0.7
3,4 <0.5 <1.2 0 (0.4,30) <3 (3.5,130) >0.98 (-0.7,0.7) (0.01,0.94) <0.7
4,5 <0.5 <1.2 0 (0.4,30) <3 (4,130) >0.98 (-0.7,0.7) (0.01,0.94) <0.7
5,8 <0.5 <1.2 0 (0.4,30) <3 (4.5,130) >0.98 (-0.7,0.7) (0.01,0.94) <0.7


2. Analysis plots: 

cos\theta^* vs mass by pT .pdf 
slope band from K0-short: .pdf 


3. Invariant Mass distribution and background estimation, side band vs. fitting 


All 4 lambda pT bins, fired jet only .pdf .txt no fired jet required .pdf .txt  

4. Extract Lambda and Anti-Lambda yields for 20 cos \theta^* , for 4 spin status, for JP1 and L2JetHigh triggers. 
Lambda pT Lambda JP1 AntiLambda JP1 Lambda L2JetHigh AntiLambda L2JetHigh
2, 3 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html
3, 4 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html
4, 5 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html
5, 8 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html
 

5. Extract DLL from the spin sorted Lambda/AntiLambda yeilds in each cos \theta^* bin, for each trigger
Lambda pT Lambda JP1 AntiLambda JP1 Lambda L2JetHigh AntiLambda L2JetHigh
2, 3 FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html
3, 4 FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html
4, 5 FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html
5, 8 FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html FiredJet .html  noFire .html


6. Fit DLL vs. cos \theta^* to extract the "DLL"


Lambda pT Lambda JP1 AntiLambda JP1 Lambda L2JetHigh AntiLambda L2JetHigh
2, 3 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html
3, 4 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html
4, 5 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html
5, 8 FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html FiredJet.pdf .txt .html  noFire .pdf .txt .html


7. DLL correction 


Appendix,  Anti-Lambda/Lambda ratio: 


3) New simulation production

Background 
Simulations performed by Ramon Cendejas. Unfortunately, an error was found in the (subdominant) process contributions when Ramon needed to move on. This and other factors held up progress since.


Introduction
  • Pure MC simulation under STAR geometry.
  • Generate pp events using Pythia 6.4.28 (Tune 320) with Lambda filter, in different partonic pT intervals and weighted by integral luminosities
  • Reconstruct Lambda based on track association
  • Jet reconstruction used CDF cone algorithm with R = 0.7


Statistics of simulation sample 
It totally took about 4.5 CPU years. 


  
Slides20170110  

Jet Cone Study 
1. slides (JP1 lambda pt2-3 for example)    
2. All comparison plots for different lambda pt bin and different Triggers 

Trigger Bias Plot 
1. updated version for cdf cone algorigthm

Data/MC comparison for
Lambda: 

lamdba pt JP1 L2JetHigh
2_3 file file
3_4 file file
4_5 file file
5_8 file file
Anti-lambda: 
A-lamdba pt JP1 L2JetHigh
2_3 file file
3_4 file file
4_5 file file
5_8 file file

QA: 
lamdba pt MB JP1 L2JetHigh
2_3 file file file
3_4 file file file
4_5 file file file
5_8 file file file

Trigger effect: (old, anti-kt R06 )
  f_z feed down parton subprocess
Lambda file1 file2 file file file
A-lambda file1 file2 file file file





 

4) Systematic uncertainties

Systematic uncertainties summary

  • decay, fz, and f_parton from simulation 
  • pile-up and residual background are from preliminary version

    η > 0   η < 0
    Lambda Anti-lambda   Lambda Anti-lambda
  pt JP1 L2J JP1 L2J   JP1 L2J JP1 L2J
decay 2.4 0.0009 0.0018 0.0001 0.0003   0.0001 0 0.0001 0.0001
3.4 0.0008 0.0011 0.0004 0.0003   0 0.0001 0 0
4.4 0.002 0.0027 0.0008 0.0008   0.0003 0.0004 0.0001 0.0002
5.9 0.0017 0.0024 0.0013 0.0022   0.0005 0.0009 0.0003 0.0007
                     
fz 2.4 0.0011 0.0028 0.0003 0.0015   0.0002 0.0001 0.0001 0.0001
3.4 0.001 0.0034 0.0006 0.0024   0.0003 0.0005 0.0003 0
4.4 0.0056 0.008 0.0053 0.0079   0.0005 0.0007 0.0009 0.0013
5.9 0.009 0.0121 0.0154 0.0191   0.0021 0.0028 0.0037 0.0046
                     
fparton 2.4 0.0005 0.0008 0.0004 0.0012   0.0001 0.0001 0.0001 0.0002
3.4 0.0011 0.0021 0.0002 0.0013   0.0003 0.0005 0 0.0003
4.4 0.0019 0.0038 0.0003 0.0011   0.0005 0.0009 0.0001 0.0003
5.9 0.0034 0.0062 0.0016 0.0027   0.0011 0.002 0.0005 0.0009
                     
pile-up 2.4 0.0182 0.0057 0.0184 0.0063   0.0182 0.0057 0.0184 0.0063
3.4 0.0023 0.0007 0.0022 0.001   0.0023 0.0007 0.0022 0.001
4.4 0.0023 0.0007 0.0022 0.001   0.0023 0.0007 0.0022 0.001
5.9 0.0068 0.0023 0.0064 0.0023   0.0068 0.0023 0.0064 0.0023
                     
bkgd 2.4 0.005 0.001 0.0001 0.0002   0.005 0.001 0.0001 0.0002
3.4 1.00E-06 0.0001 0.0001 0.0006   1.00E-06 0.0001 0.0001 0.0006
4.4 0.0007 4.00E-05 0.0004 0.0002   0.0007 4.00E-05 0.0004 0.0002
5.9 0.0002 0.0002 0.001 0.0001   0.0002 0.0002 0.001 0.0001
                     
all 2.4 0.0189 0.0067 0.0184 0.0066   0.0189 0.0058 0.0184 0.0063
3.4 0.0029 0.0042 0.0023 0.0030   0.0023 0.0010 0.0022 0.0012
4.4 0.0067 0.0093 0.0058 0.0081   0.0025 0.0014 0.0024 0.0017
5.9 0.0119 0.0140 0.0168 0.0196   0.0072 0.0042 0.0075 0.0053



2009 dijet x-sect/A_LL @ 200 GeV

 

2011 FMS Jet-like correlations @ 500 GeV

 

2011 FMS inclusive pions @ 500 GeV

 

2012 Jet A_LL @ 500 GeV

 

2012 Lambda D_TT @200GeV

 

1) Dataset and RunQA

Dataset for pp200trans_2012 D_TT analysis


Statistics Summary

Dataset: pp200trans_2012

Integrated Luminosity: 18.4 pb^-1

Selected Triggers: JP0, JP1, JP2, AJP

Event Statistics For Each Trigger:

Trigger JP0 JP1 JP2 AJP Combined
HardXSoft 2.461964e+07 8.525444e+07 1.797188e+07 1.391969e+07 1.417656e+08

Data QA

 

2) Lambda Reconstruction

The reconstruction of Lambda and anti-Lambda hyperons.

Identification cut on track’s dE/dx measured in TPC is used to find pion and (anti-)proton.

Sketch for Topological Cuts 



Values:

  a) Statistics of Lambda and anti-Lambda Reconstruction, Inclusive
  b) Statistics of Lambda and anti-Lambda Reconstruction, Jet near-side

  Only the jet near-side Lambda used to extract D_TT.

The comparison about the reconstruction status with two sets of cut are shown here.
The loose one is the cut set used in run09 D_LL analysis and the tight one.

a) Statistics of Lambda and anti-Lambda Reconstruction, Inclusive

D_TT analysis Record, Rec_Step: all_cut_crp0995

Invariant Mass

Statistics Summary

====> Lambda

 
JP0
 
 
 
JP1
 
 
 
JP2
 
 
 
AJP
 
 
 
Combined
 
 
 
pt_T [GeV/c]
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
1~2 1.1154 0.0016 364262 0.0536 1.1155 0.0016 1394859 0.0570 1.1155 0.0016 280707 0.0666 1.1155 0.0016 338322 0.0546 1.1155 0.0016 2378150 0.0572
2~3 1.1157 0.0021 96583 0.0609 1.1157 0.0021 496180 0.0654 1.1157 0.0022 122363 0.0758 1.1157 0.0021 118569 0.0631 1.1157 0.0021 833695 0.0660
3~4 1.1158 0.0027 25879 0.0612 1.1158 0.0028 186321 0.0649 1.1158 0.0028 57674 0.0748 1.1158 0.0027 38191 0.0609 1.1158 0.0028 308065 0.0659
4~5 1.1161 0.0035 6360 0.0616 1.1160 0.0034 65638 0.0644 1.1159 0.0034 25367 0.0703 1.1160 0.0035 11204 0.0565 1.1160 0.0034 108569 0.0648
5~6 1.1162 0.0041 1782 0.0791 1.1162 0.0042 25415 0.0720 1.1162 0.0042 11736 0.0745 1.1163 0.0042 3484 0.0669 1.1162 0.0042 42417 0.0726
6~8 1.1168 0.0051 729 0.0938 1.1166 0.0051 14932 0.0884 1.1166 0.0052 8622 0.0912 1.1169 0.0051 1853 0.0835 1.1166 0.0051 26136 0.0891

====> anti-Lambda

 
JP0
 
 
 
JP1
 
 
 
JP2
 
 
 
AJP
 
 
 
Combined
 
 
 
pt_T [GeV/c]
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
Central [GeV]
Width [GeV]
N_candidate
bkg fraction
1~2 1.1155 0.0015 299136 0.0755 1.1155 0.0016 1048977 0.0834 1.1155 0.0015 195241 0.0999 1.1155 0.0015 284645 0.0735 1.1155 0.0017 1827999 0.0823
2~3 1.1157 0.0020 102267 0.0676 1.1157 0.0020 468030 0.0743 1.1157 0.0021 97877 0.0931 1.1157 0.0020 114900 0.0702 1.1157 0.0020 783074 0.0751
3~4 1.1159 0.0026 26961 0.0663 1.1159 0.0026 183094 0.0680 1.1158 0.0027 46292 0.0860 1.1159 0.0027 34646 0.0694 1.1159 0.0027 290993 0.0709
4~5 1.1162 0.0033 5659 0.0660 1.1161 0.0034 61114 0.0635 1.1160 0.0034 19641 0.0741 1.1161 0.0035 8582 0.0678 1.1161 0.0034 94996 0.0662
5~6 1.1166 0.0043 1301 0.0707 1.1163 0.0041 20461 0.0756 1.1162 0.0041 8679 0.0798 1.1164 0.0041 2292 0.0794 1.1163 0.0041 32733 0.0768
6~8 1.1168 0.0057 459 0.1046 1.1168 0.0053 10175 0.1061 1.1166 0.0051 5581 0.1092 1.1172 0.0053 972 0.1086 1.1168 0.0052 17187 0.1072

Lambda candidates invariant mass distributions for each p_T range

Trigger: JP0 Distribution Statistics

Trigger: JP1 Distribution Statistics

Trigger: JP2 Distribution Statistics

Trigger: AJP Distribution Statistics

Trigger: Combined Distribution Statistics

ant-Lambda candidates invariant mass distributions for each p_T range

Trigger: JP0 Distribution Statistics

Trigger: JP1 Distribution Statistics

Trigger: JP2 Distribution Statistics

Trigger: AJP Distribution Statistics

Trigger: Combined Distribution Statistics

Distributions for p_T, eta, phi

Lambda candidates p_T, eta, phi distributions for each p_T range

Trigger: JP0 pT eta phi

Trigger: JP1 pT eta phi

Trigger: JP2 pT eta phi

Trigger: AJP pT eta phi

Trigger: Combined pT eta phi

anti-Lambda candidates p_T, eta, phi distributions for each p_T range

Trigger: JP0 pT eta phi

Trigger: JP1 pT eta phi

Trigger: JP2 pT eta phi

Trigger: AJP pT eta phi

Trigger: Combined pT eta phi

Distributions of variables used as topolagical cuts

Lambda candidates decay length, dca2, dcaV0 and cosrp distributions for each p_T range

Trigger: JP0 decay length dca2 dcaV0 cosrp

Trigger: JP1 decay length dca2 dcaV0 cosrp

Trigger: JP2 decay length dca2 dcaV0 cosrp

Trigger: AJP decay length dca2 dcaV0 cosrp

Trigger: Combined decay length dca2 dcaV0 cosrp

anti-Lambda candidates decay length, dca2, dcaV0 and cosrp distributions for each p_T range

Trigger: JP0 decay length dca2 dcaV0 cosrp

Trigger: JP1 decay length dca2 dcaV0 cosrp

Trigger: JP2 decay length dca2 dcaV0 cosrp

Trigger: AJP decay length dca2 dcaV0 cosrp

Trigger: Combined decay length dca2 dcaV0 cosrp

Distributions of variables of daughter particles

dca of daughters is also used as cut

Proton from Lambda candidates: p_T, eta, phi and dca distributions for each p_T range

Trigger: JP0 p_T eta phi dca

Trigger: JP1 p_T eta phi dca

Trigger: JP2 p_T eta phi dca

Trigger: AJP p_T eta phi dca

Trigger: Combined p_T eta phi dca

Pion from Lambda candidates: p_T, eta, phi and dca distributions for each p_T range

Trigger: JP0 p_T eta phi dca

Trigger: JP1 p_T eta phi dca

Trigger: JP2 p_T eta phi dca

Trigger: AJP p_T eta phi dca

Trigger: Combined p_T eta phi dca

Proton from anti-Lambda candidates: p_T, eta, phi and dca distributions for each p_T range

Trigger: JP0 p_T eta phi dca

Trigger: JP1 p_T eta phi dca

Trigger: JP2 p_T eta phi dca

Trigger: AJP p_T eta phi dca

Trigger: Combined p_T eta phi dca

Pion from anti-Lambda candidates: p_T, eta, phi and dca distributions for each p_T range

Trigger: JP0 p_T eta phi dca

Trigger: JP1 p_T eta phi dca

Trigger: JP2 p_T eta phi dca

Trigger: AJP p_T eta phi dca

Trigger: Combined p_T eta phi dca

3) Extraction of D_TT

D_TT extraction Procedure Plots    

 

5) Trigger Bias Study

MC samples before and after trigger conditions applying are used for trigger bias study.

  • changes in the fractional momentum z of the produced Lambda and anti-Lambda
 within the associated jet,
    changes in the relative contributions from different hard sub-processes and fragmenting partons with different flavors in the production.
    possible differences in the fraction of feed-down contributions.

Please maximize your web browser before open the following links or some plots may not show up.

1, Trigger bias parameters plots 

2, Uncertainty to D_TT from trigger bias



6) Paper proposal

Title:

Transverse spin transfer of Lambda and Anti-Lambda Hyperons in Polarized proton-proton collisonns at \sqrt{s}=200 GeV at RHIC

PAs:  Jincheng Mei,Qinghua Xu

Proposed Target Journal: Phys. Rev. D

Abstract:
The transverse spin transfer from polarized protons to Λ and ΛÌ„ hyperons is expected to provide sensitivity to the transversity distribution of the nucleon and to the transversely polarized fragmen- tation functions. We report the first measurement of the transverse spin transfer to Λ and ΛÌ„ along the polarization direction of the fragmenting quark, D_TT, in transversely polarized proton-proton collisions at sqrt{s} = 200 GeV with the STAR detector at RHIC. The data correspond to an integrated luminosity of 18 pband cover the pseudorapidity range |η| < 1.2 and transverse momenta p_up to8 GeV/c. The dependence on p_and η are presented. The D_TT results are found to be comparable with a model prediction, and are also consistent with zero within uncertainties.


Figures: 

FIG. 1: The invariant mass distribution for Lambda (open circles) and anti-Lambda (filled circles) candidates for trigger combined sample after selections with 1 <$p_{\mathrm{T}}$ < 8 GeV/c in this analysis. 



FIG. 2:
The invariant mass distribution versus cos\theta^{*} for Lambda candidates in the jet near-side with 1< p_T < 8 GeV/c in this analysis as an example.



FIG. 3:
 
The spin transfer $D _{TT}$ versus cos for a) $\Lambda$ and b) $\bar{\Lambda}$ hyperons, and c) the spin asymmetry $\delta_{TT}$ for the control sample of $K_S^0$ mesons versus cos/theta  in the $p_T$ bin of (2,3) GeV/c for triggered combined sample. The red circles show the results for positive pseudo-rapidity $\eta$ with respect to the polarized beam and the blue squares show the results for negative $\eta$. Only statistical uncertainties are shown.




FIG. 4:
 The spin transfer $D_\mathrm{TT}$ for $\Lambda$ and $\bar{\Lambda}$ versus $p_\mathrm{T}$ in polarized proton-proton collisions at $\sqrt{s}=200\,\mathrm{GeV}$ at STAR, in comparison with model predictions for (a) positive $\eta$ and (b) negative $\eta$. The vertical bars and bands indicate the sizes of the statistical and systematic uncertainties, respectively. The $\bar{\Lambda}$ results have been offset to slightly larger $p_T$ values for clarity.




Tables:


TABLE I:  Summary of selection cuts and the Λ and ΛÌ„ candidate counts and the residual background fractions in each pTbin. Here “DCA” denotes distance of closest approach, and N(σ) quantitatively measures the distance of a particle track to a certain particle band in dE/dx vs. rigidity space[28]. \ver{l} is representative of the vector from PV to Λ decay point and p⃗ is the reconstructed momentum of Λ.



Summary:
In summary, we report the first measurement on the transverse spin transfer, DTT, to Λ and Λ Ì„ in transversely polarized proton-proton collisions at \sqrt{s} = 200 GeV at RHIC. The data correspond to an integrated luminosity of 18 pb1 taken at STAR experiment in the year of 2012, which cover mid-rapidity, |η| < 1.2 and pT up to 8GeV/cThe DTT value and precision at the highest pbin, where the effects are expected to be largest, are found to be DTT = 0.031 ± 0.033(stat.) ± 0.008(sys.) for Λ and DTT = 0.034 ± 0.040(stat.) ± 0.009(sys.) for Λ Ì„ at âŸ¨η⟩ = 0.5 and ⟨pT⟩ = 6.7 GeV/cThe results for DTTare found to be consistent with zero for Λ and ΛÌ„ within uncertainties, and are also consistent with model predictions.
 
Paper draft and review:  
   Paper draft history
   Latest paper draft version:  paperDraft modified with PRD referee 

 
 PWGC review
   Collaboration review

Analysis Note:

   Analysis Note Draft

Support Materials:

   Web links:
  • Lambda reconstruction status
          1, Statistics of Lambda and anti-Lambda Reconstruction, Inclusive
          2,
 Statistics of Lambda and anti-Lambda Reconstruction, Jet near-side
  • MC production and data comparison
          1, MC production summary: hard_pT weight
          2, 
MC and data comparison for inclusive hyperons
          3, 
MC and data comparison for jet near-side hyperons
  • Trigger Bias

          1, Trigger bias parameters (fz_shift, feed-down fraction, fragmenting parton flavor fraction, subprocess fraction) plots 
          2, 
Uncertainty to D_TT from trigger bias

  Presentations:

  Proceedings:
Main Analysis Code: 



 

2012 Pi0 - Jet A_LL @ 500

 

2012 Pions in Jets A_UT @ 200 GeV

2012 dijet A_LL @ 500

2012/13 FMS A_LL @ 500 GeV

 

2013 Di-jet A_LL @ 500 GeV

 

A New Users Guide to PDSF Success

Credit goes to Kevin Adkins for the User's guide below:

With the current state of storage on RCF, several users are becoming regular users of PDSF. Anselm and others have requested that I write a short introduction to PDSF. So this blog will hold the keys for successful operation on PDSF. It will expand as issues are broght forth and addressed.

Getting started at PDSF:
1. Get your username at this website: https://nim.nersc.gov/nersc_account_request.php
Once you submit this form you will receive an email that includes a link. This link will only be valid for 72 hours, and will point you to a location where you can set your password. So don't postpone! If you have trouble the email will include a phone number to call, the staff is very helpful so don't hesitate to contact them.
2. Get logged in using the same terminal command as RCF:
ssh -Y username@pdsf.nersc.gov : where username, of course, will be your username.
3. When entering your password, you only have three chances. After your third chance you'll be "locked out" and you must call to have your password reset. To avoid the hassle, make your password something you can remember!

Storage disks at PDSF:
There are two disks that STAR-spin has access to on PDSF:
/eliza14/star/pwg/starspin/
/eliza17/star/pwg/starspin/
You must email Jeff Porter ( rjporter@bnl.gov ) with your username once you can log in. He will give you access to write on these disks. Once you have the access you can create yourself a folder to write your data to on one or both of the above disks.

Transferring data to PDSF:
PDSF has two Data Transfer Nodes (DTN) that are dedicated to the transfer of data at a high rate. These are
pdsfdtn1.nersc.gov
pdsfdtn2.nersc.gov
Transferring data is best with the rsync command. As an example, assume we have several subdirectories of jets stored in /star/data05/scratch/jkadkins/run12_Jets/ on RCF. To transfer this directory as is to the directory /eliza17/star/pwg/starspin/jkadkins/ on PDSF we would use:
rsync -r -v /star/data05/scratch/jkadkins/run12_Jets jkadkins@pdsfdtn1.nersc.gov:/eliza17/star/pwg/starspin/jkadkins/
Note that I left off the "/" at the end of the run12_Jets directory above. This means that we will copy all subdirectories to PDSF in the same structure. If the directory at PDSF doesn't exist, it will be created. If there is data already in a directory of the same name on PDSF then the new data will simply be added. If we had left "/" on the end of run12_Jets then we would have copied all files and subdirectories to /eliza17/star/pwg/starspin/jkadkins and not group it into a directory named run12_Jets on PDSF. Give it a test with a few files in a directory to see exactly how this works. 
Note: Transferring large volumes of data takes time. To transfer ~90 gigs of data it will take ~60 minutes. So transferring large jet trees or something similar can take a really long time. It may be best to break it up into smaller segments that are more time manageable.

Running code on PDSF:
Code runs EXACTLY the same on PDSF as it does on RCF. PDSF has the same CVS code up to date as on RCF (I'm not sure how often it's updated, but it's all there). So if you use code in CVS on RCF, then you can also use it on PDSF. The only thing that changes is that PDSF doesn't support is the STAR development library. So when running you'll need to use "starpro" or another library. 
Submitting jobs is also EXACTLY the same. You'll need an XML (if it works on RCF, it'll work on PDSF without changes) and you'll use the same star-submit command that you use on RCF. The changes come when you want to check the status of your jobs. The two most common commands to manage jobs are:
qstat -u username : Check the status of all jobs you have submitted
qdel -u username : Remove all jobs you currently have submitted
A full list of queue commands can be found here: http://www.nersc.gov/users/computational-systems/pdsf/using-the-sge-batch-system/monitoring-and-managing-jobs/

Finally, problems should be reported to the PDSF hypernews ( pdsf-hn@sun.star.bnl.gov ).

Analyses from the early years

 

(A) List of Physics Analysis Projects (obsolete)

Who Institution Data Topic
Jan Balewski MIT 2009 W production
Michael Betancourt MIT 2009/6   prompt gamma mid-rap A_LL/cross sec.
Alice Bridgeman ANL 2009 EEMC gammas
Thomas Burton Birmingham   2006 Lambda trans. pol.
Ramon Cendejas UCLA/LBL 2008 di-jet cross section
Ross Corliss MIT 2006/9 photons 1
Pibero Djawotho TAMU 2009 inclusive and di-jet
Xin Dong LBL    
Jim Drachenberg TAMU 2008 FMS+FTPC jets Sivers/Collins
Len Eun PSU 2006/8 eta SSA
Robert Fersch Kentucky 2009/6 tbd /mid-rapidity jet Collins
Oleksandr Grebenyuk LBL 2009/6 TBD/pi0
Weihong He IUCF 2006 EEMC pi0
Alan Hoffman MIT 2005/6 neutral pions A_LL
Liaoyuan Huo TAMU 2009 inclusive and di-jet
Christopher Jones MIT 2009/6 inclusive jets A_LL/cross section
Adam Kocoloski MIT 2005/6 charged pions A_LL
Priscilla Kurnadi UCLA 2006 non photonic electron A_LL
William Leight MIT 2009 Mid-rapidity hadron production
Xuan Li Shandong U   hyperons
Brian Page IUCF 2009 dijets
Donika Plyku ODU 2009 Spin dep. in pp elastic scattering from pp2pp
Nikola Poljak Zagreb 2006/8 Collins Sivers separation forward SSA
Tai Sakuma MIT 2005/6 dijets cross section/A_LL
Joe Seele MIT 2009 Ws and dijet cross section
Ilya Selyuzhenkov IUCF 2006-9 Forward gamma-jet
David Staszak UCLA 2006 Inclusive Jet A_LL
Justin Stevens IUCF 2010 TBD
Naresh Subba KSU 2006 Non-Photonic Elect. 1>eta>1.5 xsec
Matthew Walker MIT 2006/9 dijets cross section/A_LL
Grant Webb Kentucky 2009/6 mid-rap gamma or di-jet/ UEvent
Wei Zhou Shandong U   hyperons
Wei-Ming Zhang KSU 2008 non-photonic electrons EEMC A_LL

 

Common Analysis Trees

The Spin PWG maintains a set of trees connecting datasets from the various inclusive measurements in a way that allows for easy particle correlation studies. This page describes how to access the data in those trees.

Location

RCF:    /star/institutions/mit/common/run6/spinTree/
PDSF:   /auto/pdsfdv34/starspin/common/run6/spinTree/
Anywhere:   root://deltag5.lns.mit.edu//Volumes/scratch/common/run6/spinTree/spinAnalyses_runnumber.tree.root

The last option uses xrootd to access read-only files stored on an MIT server from any computer with ROOT installed.  If you have an Intel Mac note that ROOT versions 5.13.06 - 5.14.00 have a bug (patched in 5.14.00/b) that prevents you from opening xrootd files.

Interactive Mode

The basic trees are readable in a simple interactive ROOT session.  Each particle type is stored in a separate tree, so you need to use TTree::AddFriend to connect things together before you draw.  For example:

root [1] TFile::Open(&quot;root://deltag5.lns.mit.edu//Volumes/scratch/common/run6/spinTree/spinAnalyses_7156028.tree.root&quot;); root [2] .ls TXNetFile** root://deltag5.lns.mit.edu//Volumes/scratch/common/run6/spinTree/spinAnalyses_7156028.tree.root TXNetFile* root://deltag5.lns.mit.edu//Volumes/scratch/common/run6/spinTree/spinAnalyses_7156028.tree.root KEY: TProcessID ProcessID0;1 00013b6e-72c3-1640-a0e8-e5243780beef KEY: TTree spinTree;1 Spin PWG common analysis tree KEY: TTree ConeJets;1 this can be a friend KEY: TTree ConeJetsEMC;1 this can be a friend KEY: TTree chargedPions;1 this can be a friend KEY: TTree bemcPions;1 this can be a friend root [3] spinTree-&gt;AddFriend(&quot;ConeJets&quot;); root [4] spinTree-&gt;AddFriend(&quot;chargedPions&quot;); root [5] spinTree-&gt;Draw(&quot;chargedPions.fE / ConeJets.fE&quot;,&quot;chargedPions.fE&gt;0&quot;) If you have the class definitions loaded you can also access member functions directly in the interpreter:

root [6] spinTree-&gt;Draw(&quot;chargedPions.Pt() / ConeJets.Pt()&quot;,&quot;chargedPions.Pt()&gt;0&quot;)

Batch Mode

The StSpinTreeReader class takes care of all the details of setting branch addresses for the various particles behind the scenes.  It also allows you to supply a runlist and a set of triggers you're interested in, and it will only read in the events that you care about.  The code lives in

StRoot/StSpinPool/StSpinTree

and in the macros directory is an example showing how to configure it.  Let's look at the macro step-by-step:

//create a new reader StSpinTreeReader *reader = new StSpinTreeReader(); //add some files to analyze, one at a time or in a text file reader-&gt;selectDataset(&quot;$STAR/StRoot/StSpinPool/StSpinTree/datasets/run6_rcf.dataset&quot;); //reader-&gt;selectFile(&quot;./spinAnalyses_6119039.tree.root&quot;); Ok, so we created a new reader and told it we'd be using the files from Run 6 stored on RCF.  You can also give it specfic filenames if you'd prefer, but there's really no reason to do so.

//configure the branches you're interested in (default = true) reader-&gt;connectJets = true; reader-&gt;connectNeutralJets = false; reader-&gt;connectChargedPions = true; reader-&gt;connectBemcPions = true; reader-&gt;connectEemcPions = false; reader-&gt;connectBemcElectrons = false; //optionally filter events by run and trigger //reader-&gt;selectRunList(&quot;$STAR/StRoot/StSpinPool/StSpinTree/filters/run6_jets.runlist&quot;); reader-&gt;selectRun(7143025); //select events that passed hardware OR software trigger for any trigger in list reader-&gt;selectTrigger(137221); reader-&gt;selectTrigger(137222); reader-&gt;selectTrigger(137611); reader-&gt;selectTrigger(137622); reader-&gt;selectTrigger(5); //we can change the OR to AND by doing reader-&gt;requireDidFire = true; reader-&gt;requireShouldFire = true; In this block we configured the reader to pick up the jets, chargedPions and BEMC pi0s from the files. We also told it that we only wanted to analyze run 7132001, and that we only cared about events triggered by BJP1, L2jet, or L2gamma in the second longitudinal running period.  Finally, we required that one of those trigIds passed both the hardware and the software triggers.

After that, the reader behaves pretty much like a regular TChain.  The first time you call GetEntries() will be very slow (few minutes for the full dataset) as that's when the reader chains together the files and applies the TEventList with your trigger selection.  Each of the particles is stored in a TClonesArray, and the StJetSkimEvent is accessible via reader->event().

StJetSkimEvent *ev = reader-&gt;event(); TClonesArray *jets = reader-&gt;jets(); TClonesArray *chargedPions = reader-&gt;chargedPions(); TClonesArray *bemcPions = reader-&gt;bemcPions(); long entries = reader-&gt;GetEntries(); for(int i=0; i

What's Included?

Common trees are produced for both Run 5 and the 2nd longitudinal period of Run 6. Here's what available:

Run 5
  1. skimEvent
  2. ConeJets
  3. chargedPions
  4. bemcPions
Run 6
  1. skimEvent
  2. ConeJets12
  3. ConeJetsEMC
  4. chargedPions -- see (Data Collection)
  5. bemcPions
  6. bemcElectrons

Known Issues

The first time you read a charged pion (batch or interactive) you may see some messages like

Error in <tclass::new>: cannot create object of class StHelix</tclass::new>

These are harmless (somehow related to custom Streamers in the StarClassLibrary) but I haven't yet figured out how to shut them up.

42 runs need to be reprocessed for chargedPions in Run 5.  Will do once Andrew gives the OK at PDSF.

40 runs need to be reprocessed for Run 6 because of MuDst problems.  Murad has also mentioned some problems with missing statistics in the skimEvents and jet trees that we'll revisit at a later date.

Future Plans

Including EEMC pi0s and StGammaCandidates remains on my TO-DO list.  I've also added into StJet a vector of trigger IDs fired by that jet.  Of course we also need to get L2 trigger emulation into the skimEvent.  As always, if you have questions or problems please feel free to contact me.  

Cuts Summary

Here's a list of the cuts applied to the data in the common spin trees.

Run 5

Event
  • standard spinDB requirements
  • production triggers only
ConeJets
  • 0.2 < detEta < 0.8
  • 0.1 < E_neu / E_tot < 0.9
chargedPions
  • pt > 2
  • -1 < eta < 1
  • nFitPoints > 25
  • |DCA_global| < 1
  • -1 < nSigmaPion < 2
bemcPions
  • pt > 3.0
  • photon energies > 0.1
  • asymmetry < 0.8
  • 0.08 < mass < 0.25
  • charged track veto
  • BBC timebin in {7,8,9}

Run 6

Event
  • standard spinDB requirements
  • production triggers + trigId 5 (L2gamma early runs)
ConeJets, ConeJetEMC -- no cuts applied

chargedPions
  • pt > 2
  • -1 < eta < 1
  • nFitPoints > 25
  • |DCA_global| < 1
  • -1 < nSigmaPion < 2
bemcPions
  • pt > 5.2
  • photon energies > 0.1
  • asymmetry < 0.8
  • 0.08 < mass < 0.25
  • charged track veto
  • BBC timebin in {7,8,9} update:  timebin 6 added in 2007-07-18 production
  • both SMD planes good
bemcElectrons added as of 2007-07-18 production
  • hardware or software trigger in (117001, 137213, 137221, 5, 137222, 137585, 137611, 137622)
  • Global dE/dx cut changing with momentum
  • nFitPoints >= 15
  • nDedxPoints >= 10
  • nHits / nPoss >= 0.52
  • track Chi2 < 4
  • DCAGlobal < 2
  • NEtaStrips > 1 && NPhiStrips > 1
  • Primary dE/dx cut changing with momentum
  • 0.3 < P/E < 1.5
  • -0.01287 < PhiDist < 0.01345
  • ZDist in [-5.47,1.796] (West) or [-2.706,5.322] (East)

Introduction at Spin PWG meeting - 5/10/07

I've been working on a project to make the datasets from the various longitudinal spin analyses underway at STAR available in a common set of trees.  These trees would improve our ability to do the kind of correlation studies that are becoming increasingly important as we move beyond inclusive analyses in the coming years.

In our current workflow, each identified particle analysis has one or more experts responsible for deciding just which reconstruction parameters and cuts are used to determine a good final dataset.  I don't envision changing that.  Rather, I am taking the trees produced by those analyzers as inputs, picking off the essential information, and feeding it into a single common tree for each run.  I am also providing a reader class in StSpinPool that takes care of connecting the various branches and does event selection given a run list and/or trigger list.

Features

  • Readable without the STAR framework
  • Condenses data from several analyses down to the most essential ~10 GB (Run 6)
  • Takes advantage of new capabilities in ROOT allowing fast fill/run/trigger selection

Included Analyses

  • Event information using StJetSkimEvent
  • ConeJets12 jets (StJet only)
  • ConeJetsEMC jets (StJet only)
  • charged pions (StChargedPionTrack)
  • BEMC neutral pions (TPi0Candidate)
  • EEMC neutral pions (StEEmcPair?) -- TODO
  • electrons * -- TODO
  • ...

Current Status

I'm waiting on the skimEvent reproduction to finish before releasing.  I've got the codes to combine jets, charged pions, and BEMC pions, and I'm working with Jason and Priscilla on EEMC pions and BEMC electrons.

EEMC Direct Photon Studies (Pibero Djawotho, 2006-2008)

Everything as a single pdf file (341 pages, 8.2Mb)

2006.07.31 First Look at SMD gamma/pi0 Discrimination

 

Pibero Djawotho

 

Indiana University
July 31, 2006

Simulation

Simulation were done by Jason for the SVT review.

Maximal side residual

Figure 1: Fitted peak integral vs. fit residual sum (U+V) from st_jpsi input stream (J/psi trigger only). Figure 2: Fitted peak integral vs. fit residual sum (U+V) from st_physics input stream (all triggers except express stream triggers).

xy distribution of SMD hits

The separation between photons and pions was achieved by using Les cut in the above figures where photons reside above the curve and pions below. The data set used is the st_jpsi express stream.

Single peak characteristics

Fit function

The transverse profile of an electromagnetic shower in the SMD can be parametrized by the equation below in each SMD plane:

f(x) is the energy in MeV as a function of SMD strip x. The algorithm performs a simultaneous fit in both the U and V plane. The maximal residual (data - fit) is then calculated. A single photon in the SMD should be well descibed by the equation above and therefore will have a smaller maximal residual. A neutral pion, which decays into two photons, should exhibit a larger maximal residual. Typically, the response would be a double peak, possibly a larger peak and a smaller peak corresponding to a softer photon.

Single event SMD response

This directory contains images of single event SMD responses in both U and V plane. The file name convention is SMD_RUN_EVENT.png. The fit function for a single peak is the one described in the section above with 5 parameters:

  • p0 = yield (P0), area under the peak in MeV
  • p1 = mean (μ), center of peak in strips
  • p2 = sigma of the first Gaussian (w1)
  • p3 = fraction of the amplitude of the second Gaussian with respect to the first one (B), fixed to 0.2
  • p4 = ratio of the width of the second Gaussian to the width of the first one (w2/w1), fixed to 3.5

Code

macros

Documents

  1. Proposal to Contstruct an Endcap Calorimeter for Spin Physics at STAR
  2. Appendix Simulation Studies of Direct Photon Production at STAR
  3. An Endcap Calorimeter for STAR Conceptual Design Report
  4. The STAR Endcap Electromagnetic Calorimeter (EEMC NIM)
  5. An Endcap Calorimeter for STAR Technical Design Update #1
  6. Jan's gamma/pi0 algorithm
  7. Endcap Calorimeter Proposal (HTML @ IUCF)
  8. STAR Note 401: An Endcap Electromagnetic Calorimeter for STAR--Conceptual Design Report
  9. Spin Effects at Suppercollider Energies

2006.08.04 Second Look at SMD gamma/pi0 Discrimination

 

Second Look at SMD gamma/pi0 Discrimination

Pibero Djawotho
Indiana University
August 4, 2006

Dataset

The dataset used in this analysis is the 2005 p+p collision at √s=200 GeV with the endcap calorimeter high-tower-1 (eemc-ht1-mb = 96251) and high-tower-2 (eemc-ht2-mb = 96261) triggers.

The file catalog query used to locate the relevant files is:
get_file_list.pl -keys 'path,filename' -delim / -cond 'production=P05if, trgsetupname=ppProduction,filetype=daq_reco_MuDst,filename~st_physics, tpc=1,eemc=1,sanity=1' -delim 0

Results

SMD U and V Fits

Code

macros

2006.08.06 Comparison between EEMC fast and slow simulator

 

Comparison between EEMC fast and slow simulator

Pibero Djawotho
Indiana University
August 6, 2006

A detailed description of the EEMC slow simulator is presented at the STAR EEMC Web site.

The following settings were used in running the slow simulator:

  //--
  //-- Initialize slow simulator
  //--
  StEEmcSlowMaker *slowSim = new StEEmcSlowMaker("slowSim");
  slowSim->setDropBad(1);   // 0=no action, 1=drop chn marked bad in db
  slowSim->setAddPed(1);    // 0=no action, 1=ped offset from db
  slowSim->setSmearPed(1);  // 0=no action, 1=gaussian ped, width from db
  slowSim->setOverwrite(1); // 0=no action, 1=overwrite muDst values
  slowSim->setSource("StEvent");

  slowSim->setSinglePeResolution(0.1);
  slowSim->setNpePerMipSmd(2.0);
  slowSim->setNpePerMipPre(3.9);
  slowSim->setMipElossSmd(1.00/1000);
  slowSim->setMipElossPre(1.33/1000);

EEMC Fast Simulator

EEMC Slow Simulator

2006.09.15 Fit Parameters

 

Fit Parameters

Fit Function

The plots that follow are sums of individual SMD responses in each plane centered around a common mean (here 0), over a +/-40 strips range. The convention for the parameters in the fits below is:

  • p0=E -- area under the curve which represents energy in MeV
  • p1=μ -- mean
  • p2=σcore -- width of the narrow Gaussian
  • p3=γ -- relative contribution of the wide Gaussian to the area/height
  • p4=σtail -- width of the wide Gaussian

Simulation

The simulation is from single photons thrown at the EEMC with the following pT distribution:

The highest tower above 4 GeV in total energy is selected and the corresponding SMD sector fitted for peaks in both planes, where the area of the peaks in the U plane is constrained to be identical to that of the peak in the V plane. The peak is shifted to be centered at 0 where peaks from other events are then summed. The summed SMD response in each plane is displayed below:

Ditto in log scale.

Ditto by sector.

Fit Widths

Sector # SMD-u σcore SMD-u σtail SMD-v σcore SMD-v σtail
Sector 1 0.869033 ± 0.0142868 3.42031 ± 0.10226 0.84379 ± 0.0185107 3.03287 ± 0.0775009
Sector 2 0.814959 ± 0.0169271 2.99941 ± 0.0730426 0.889892 ± 0.0163065 3.35288 ± 0.0911979
Sector 3 0.84862 ± 0.0148706 3.07648 ± 0.0909689 0.914377 ± 0.014706 3.72821 ± 0.0966915
Sector 4 0.924398 ± 0.0144207 3.74458 ± 0.10611 0.888146 ± 0.0180771 3.06618 ± 0.0647075
Sector 5 0.934218 ± 0.0163887 3.45149 ± 0.0944309 0.911209 ± 0.0175273 3.28633 ± 0.0890581
Sector 6 0.797976 ± 0.0148133 3.20464 ± 0.0986085 0.822437 ± 0.018835 3.30595 ± 0.118813
Sector 7 0.836936 ± 0.0150085 3.28589 ± 0.0853598 0.873338 ± 0.0173883 3.16654 ± 0.0838938
Sector 8 0.828403 ± 0.0167005 3.05517 ± 0.075584 0.891045 ± 0.0152102 3.34806 ± 0.0836394
Sector 9 0.832881 ± 0.0127855 3.3214 ± 0.0762928 0.8436 ± 0.0175466 3.0183 ± 0.079444
Sector 10 0.804059 ± 0.0160906 3.0943 ± 0.0897946 0.874845 ± 0.015788 3.18113 ± 0.0748357
Sector 11 0.930286 ± 0.0187086 3.40024 ± 0.0951671 0.854395 ± 0.0167265 3.21076 ± 0.0812402
Sector 12 3.33227 ± 0.111911 0.848668 ± 0.0142344 0.895174 ± 0.0160939 3.48527 ± 0.12061

Data from 2005 pp200 EEMC HT 1 and 2 triggers

In this sample, high tower triggers, eemc-ht1-mb (96251) and eemc-ht2-mb (96261), from the 2005 p+p at √s=200 GeV ppProduction are selected. The highest tower above 4 GeV is chosen and the corresponding SMD sector is searched for peaks in both planes. Peaks from several events are summed together taking care of shifting them around to have a common mean.

Ditto in log scale.

Data from 2005 pp200 electrons

Here, I try to pick a representative sample of electrons from the 2005 pp200 dataset. The cuts used to pick out electrons are:

  • Epreshower1 > 5 MeV
  • Epreshower2 > 5 MeV
  • 0.75 < p/Etower < 1.25
  • 3 < dE/dx < 4 keV/cm

The selection for electrons is illustrated in the dE/dx plot below, where the pions should be on the left and the electrons on the right.


Pibero Djawotho
Last modified Tue Aug 15 10:41:19 EDT 2006

2007.02.05 Reconstructed/Monte Carlo Photon Energy

 

Reconstructed/Monte Carlo Photon Energy

This study is motivated by Weihong's photon energy loss study where an eta-dependence of reconstructed photon energy to generated photon energy in EEMC simulation was observed.

In this study, the eta-dependence is investigated by running the EEMC slow simulator with the new readjusted weights for the preshower and postshower layers of the EEMC. Details on this are here.

    • Fit to a constant

    • Fit to a line

    • Fit to a quadratic

    • Comparison between Weihong's and Pibero's results

    The parameters from the fits are used to plot the fit functions for comparison between Weihong's and Pibero's results.

      • Constant

      • Linear

      • Quadratic

    • Conclusion

    While the adjusted weights for the different EEMC layers contribute to bringing the ratio of reconstructed energy to generated energy closer to unity, they do not remove the eta-dependence.

    • References

    1. M. Albrow et al., NIM A 480 (2002) 524-546.
    2. R. Blair et al. (CDF Collaboration), CDF II Technical Design Report, FERMILAB-PUB-96-390-E, 1996.

    Pibero Djawotho
    Last updated Mon Feb 5 10:10:42 EST 2007

2007.02.08 E_reco / E_mc vs. eta

 

E_reco / E_mc vs. eta

Legend

  • black curve: before EEMC slow simulator
  • red curve: after EEMC slow simulator

Jason's Monte Carlo

  • 4.4k single gamma's
  • No SVT
  • Nominal vertex
  • Flat in pt 4-12 GeV

Will's Monte Carlo

  • 10k single gamma's
  • SVT/SSD out
  • Vertex at 0
  • Flat in pt 5-60 GeV

In the plot below, I use the energy of the single tower (tower with max energy) presumably the tower the photon hit. The nonlinearity seems to disappear.

In the plot below, I use the energy of the 3x3 cluster of tower centered around the tower with the max energy. The nonlinearity is restored.

The plot below shows Etower/Ecluster vs. eta where the cluster consists of 3x3 towers centered around the max energy tower.

Below is the profile of E_tower/E_cluster vs. eta.

The plot below shows the energy sampled by the entire calorimeter as a function of eta, i.e. sampling fraction as a function of eta.

Sampling fraction integrated over all eta's.


Pibero Djawotho
Last updated Thu Feb 8 13:59:29 EST 2007

2007.02.11 Reconstructed/Monte Carlo Muon Energy

 

Reconstructed/Monte Carlo Muon Energy

10k muons thrown by Will with:

  • zvertex=0
  • Flat in pT 5-60 GeV/c
  • Flat in η 1.1-2

zvertex

pT vs. η

EMC

Etower/EMC vs. η

Ecluster/EMC vs. η

Etowertanh(eta) vs. eta


Pibero Djawotho
Last modified Sun Feb 11 19:51:55 EST 2007

2007.02.15 160 GeV photons

 

160 GeV photons

 

  • 10k 160 GeV photons
  • zvertex=0
  • η range 0.8-2.2
  • SVT/SSD out


Pibero Djawotho
Last updated Thu Feb 15 04:33:09 EST 2007

2007.02.15 20 GeV photons

 

20 GeV photons

 

  • 10k 20 GeV photons
  • zvertex=0
  • η range 0.8-2.2
  • SVT/SSD out


Pibero Djawotho
Last updated Thu Feb 15 04:32:25 EST 2007

2007.02.15 80 GeV photons

 

80 GeV photons

 

  • 10k 80 GeV photons
  • zvertex=0
  • η range 0.8-2.2
  • SVT/SSD out


Pibero Djawotho
Last updated Thu Feb 15 03:16:54 EST 2007

2007.02.15 Reconstructed/Monte Carlo Electron Energy

 

Reconstructed/Monte Carlo Electron Energy

E=1 GeV

E=2 GeV


Pibero Djawotho
Last modified Thu Feb 15 00:42:30 EST 2007

2007.02.19 10 GeV photons

 

10 GeV photons

 

  • 10k 10 GeV photons
  • zvertex=0
  • η range 0.8-2.2
  • SVT/SSD out


Pibero Djawotho
Last updated Mon Feb 19 20:35:13 EST 2007

2007.02.19 40 GeV photons

 

40 GeV photons

 

  • 10k 40 GeV photons
  • zvertex=0
  • η range 0.8-2.2
  • SVT/SSD out


Pibero Djawotho
Last updated Mon Feb 19 20:37:37 EST 2007

2007.02.19 5 GeV photons

 

5 GeV photons

 

  • 10k 5 GeV photons
  • zvertex=0
  • η range 0.8-2.2
  • SVT/SSD out


Pibero Djawotho
Last updated Mon Feb 19 20:13:39 EST 2007

2007.02.19 Summary of Reconstructed/Monte Carlo Photon Energy

 

Summary of Reconstructed/Monte Carlo Photon Energy

 

Description

The study presented here uses Monte Carlo data sets generated by Will Jacobs at different photon energies (5, 10, 20, 40, 80, 160 GeV):

  • 10k photons
  • vertex at 0
  • eta 0.8-2.2
  • SVT/SSD out

For each photon energy, the ratio E_reco/E_MC vs. eta was plotted and fitted to the function p0+p1*(1-eta), where E_reco is the reconstructed photon energy integrated over the

entire

EEMC. The range of the fit was fixed from 1.15 to 1.95 to avoid EEMC edge effects. The advantage of parametrizing the eta-dependence of the ratio in this way is that p0 is immediately interpretable as the ratio in the middle of the EEMC. The parameters p0 and p1 vs. photon energy were subsequently plotted for the EEMC fast and slow simulator.

EEMC Fast/Slow Simulator Results

Conclusions

The parameter p0, i.e. the ratio E_reco/E_MC in the mid-region of the EEMC, increases monotonically from 0.74 at 5 GeV to 0.82 at 160 GeV, and the parameter p1, i.e. the slope of the eta-dependence, also increases monotonically from -0.035 at 5 GeV to 0.038 at 160 GeV. There appears to be a magic energy around 10 GeV where the response of the EEMC is nearly flat across its entire pseudorapidity range. The anomalous slope p1 at 160 GeV for the EEMC slow simulator is an EEMC hardware saturation effect. The EEMC uses 12-bit ADC's for reading out tower transverse energies and is set for a 60 GeV range. Any particle which deposits more than 60 GeV in E_T will be registered as depositing only 60 GeV as the ADC will return the maximum value of 4095. This translates into a limit on the eta range of the EEMC for a particular energy. Let's say that energy is 160 GeV and the EEMC tops at 60 GeV in E_T, then the minimum eta is acosh(160/60)=1.6. This limitation is noticeable in a plot of E_reco/E_MC vs. eta. This anomaly is not observed in the result of the EEMC fast simulator because the saturation behavior was not implemented at the time of the simulation (it has since been corrected). The energy-dependence of the parameter p0 is fitted to p0(E)=a+b*log(E) and the parameter p1 to p1(E)=a+b/log(E). The results are summarized below:

EEMC fast simulator fit p0(E)=a+b*log(E)
a = 0.709946 +/- 0.00157992
b = 0.022222 +/- 0.000501239

EEMC slow simulator fit p0(E)=a+b*log(E)
a = 0.733895 +/- 0.00359237
b = 0.0177537 +/- 0.0011397

EEMC fast simulator fit p1(E)=a+b/log(E)
a = 0.0849103 +/- 0.00556979
b = -0.175776 +/- 0.0138241

EEMC slow simulator fit p1(E)=a+b/log(E)
a = 0.0841488 +/- 0.0052557
b = -0.187769 +/- 0.0130445

Pibero Djawotho
Last updated Mon Feb 19 23:18:44 EST 2007

2007.05.24 gamma/pi0 separation in EEMC using linear cut

 

gamma/pi0 separation in EEMC using linear cut


Pibero Djawotho
Last updated Thu May 24 04:41:13 EDT 2007

2007.05.24 gamma/pi0 separation in EEMC using quadratic cut

 

gamma/pi0 separation in EEMC using quadratic cut


Pibero Djawotho
Last updated Thu May 24 04:41:13 EDT 2007

2007.05.24 gamma/pi0 separation in EEMC using quadratic cut

 

gamma/pi0 separation in EEMC using quadratic cut


Pibero Djawotho
Last updated Thu May 24 04:41:13 EDT 2007

2007.05.30 Efficiency of reconstructing photons in EEMC

 

Efficiency of reconstructing photons in EEMC

Monte Carlo sample

  • 10k photons
  • STAR y2006 geometry
  • z-vertex=0
  • Flat in pt 10-30 GeV
  • Flat in eta 1.0-2.1

SMD gamma/pi0 discrimination algorithm

The following

slide

from the IUCF STAR Web site gives a brief overview of the SMD gamma/pi0 discrimination algorithm using the method of maximal sided fit residual (data - fit). This technique comes to STAR EEMC from the Tevatron via Les Bland via Jason Webb. The specific fit function used in this analysis is:

f(x)=[0]*(0.69*exp(-0.5*((x-[1])/0.87)**2)/(sqrt(2*pi)*0.87)+0.31*exp(-0.5*((x-[1])/3.3)**2)/(sqrt(2*pi)*3.3))

x is the strip id in the SMD-u or SMD-v plane. The widths of the narrow and wide Gaussians are determined from empirical fits of shower shape response in the EEMC from simulation.

Optimizing cuts for gamma/pi0 separation

In the rest of this analysis, only those photons which have reconstructed pt > 5 GeV are kept. There is no requirement that the photon doesn't convert. The dividing curve between photons and pions is:

f(x)=4*x+1e-7*x**5

The y-axis is integrated yield over the SMD-u and SMD-v plane, and the x-axis is the sum of the maximal sided residual of the SMD-u and SMD-v plane.

Following exchanges with Scott Wissink, the idea is to move from a quintic to a quadratic to reduce the number of parameters. In addition, the perpendicular distance between the curve and a point in the plane is used to estimate the likelihood of a particle being a photon or pion. Distances above the curve are positive and those below are negative. The more positive the distance, the more likely the particle is a photon. The more negative the distance, the more likely the particle is a pion.

Hi Pibero,

With your new "linear plus quintic" curve (!) ... how did you choose the
coefficients for each term?  Or even the form of the curve?  I'm not
being picky, but how to optimize such curves will be an important issue
as we (hopefully soon) move on to quantitative comparisons of efficiency
vs purity.

As a teaser, please see attached - small loss of efficiency, larger gain
in purity.

Scott

Hi Pibero,

I just worked out the distance of closest approach to a curve of the form

    y(x) = a + bx^2

and it involves solving a cubic equation - so maybe not so trivial after
all.  But if you want to pursue this (not sure it is your highest
priority right now!), the cubic could be solved numerically and "alpha"
could be easily calculated.

More fun and games.

Scott
Hi Pibero,

I played around with the equations a bit more, and I worked out an
analytic solution.  But a numerical solution may still be better, since
it allows more flexibility in the algebraic form of the 'boundary' line
between photons and pions.

Here's the basic idea:  suppose the curved line that cuts between
photons and pions can be expressed as y = f(x).  If we are now given a
point (x0,y0) in the plane, our goal is to find the shortest distance to
this line.  We can call this distance d (I think on your blackboard we
called it alpha).

To find the shortest distance, we need a straight line that passes
through (x0,y0) and is also perpendicular to the curve f(x).  Let's
define the point where this straight line intersects the curve as
(x1,y1).  This means (comparing slopes)

    (y1 - y0) / (x1 - x0) = -1 / f'(x1)

where f'(x1) is the derivative of f(x) evaluated at the point (x1,y1). 
Rearranging this, and using y1 = f(x1), yields the general result

    f(x1) f'(x1)  -  y0 f'(x1)  +   x1  -   x0  =  0

So, given f(x) and the point (x0,y0), the above is an equation in only
x1.  Solve for x1, use y1 = f(x1), and then the distance d of interest
is given by

    d = sqrt[ (x1 - x0)^2 + (y1 - y0)^2 ]

Example:  suppose we got a reasonable separation of photons and pions
using a curve of the form

    y = f(x) = a + bx^2

Using this in the above general equation yields the cubic equation

    (2b^2) x1^3  +  (2ab + 1 - 2by0) x1  -  x0  =  0

Dividing through by 2b^2, we have an equation of the form

    x^3 + px + q = 0

This can actually be solved analytically - but as I mentioned, a
numerical approach gives us more flexibility to try other forms for the
curve, so this may be the way to go.  I think (haven't proved
rigorously) that for positive values of the constants a, b, x0, and y0,
the cubic will yield three real solutions for x1, but only one will have
x1 > 0, which is the solution of interest.

Anyway, it has been an interesting intellectual exercise!

Scott

I made use of the ROOT function TMath::RootsCubic to solve the cubic equation numerically for computing distances of each point to the curve. With the new quadratic curve f(x)=100+0.1*x^2 the efficiency is 63% and the rejection is 82%.

Efficiency and Rejection

The plot on the left below shows the efficiency of identifying photons over the pt range of 10-30 GeV and the one on the right shows the rejection rate of single neutral pions. Both average about 75% over the pt range of interest.

Rejection vs. efficiency at different energies

The plot below shows background rejection vs. signal efficiency for different energy ranges of the thrown gamma/pi0.

Rejection vs. efficiency with preshower cut

Below on the left is a plot of the ratio of the sum of preshower 1 and 2 to tower energy for both photons (red) and pions (blue). On the right is the rejection of pions vs. efficiency of photons as I cut on the ratio of preshower to tower. It is clear from these plots that the preshower layer is not a good gamma/pi0 discriminator, although can be used to add marginal improvement to the separation preovided by the shower max.

ALL ENERGIES

E=20-40 GeV

E=40-60 GeV

E=60-80 GeV

E=80-90 GeV


Pibero Djawotho
Last updated Wed May 30 00:32:16 EDT 2007

2007.06.12 gamma/pi0 separation in EEMC at pT 5-10 GeV

 

gamma/pi0 separation in EEMC at pT 5-10 GeV


Pibero Djawotho
Last updated Tue Jun 12 11:59:42 EDT 2007

2007.06.28 Photons in Pythia

Pythia Simulations

 

Pythia Simulations


All partonic pT

The plots below show the distribution of clusters in the endcap calorimeter for different partonic pT ranges. 2000 events were generated for each pT range. A cluster is made up of a central high tower above 3 GeV in pT and its surounding 8 neighbors. The total cluster pT must exceed 4.5 GeV.

pT=9-11 GeV

Below is the pT of direct and decay photons from the Pythia record. Note how the two subsets are well separated at a given partonic pT. Any contamination to the direct photon signal would have to come from higher partonic pT.

Differences between Renee's and Manuel's Pythia records?

Number of prompt photons per event from GEANT record


Pibero Djawotho
Last updated Fri Jun 8 16:08:27 EDT 2007

a_LL

 

Partonic aLL

Jet

Gamma


Pibero Djawotho
Last updated Sat Jun 30 20:14:21 EDT 2007

gamma pT=9-11 GeV

 

gamma pT=9-11 GeV


Pibero Djawotho
Last modified Fri Jul 6 10:48:39 EDT 2007

gamma-jet kinematics

 

gamma-jet kinematics


Clusters without parent track

Pibero Djawotho
Last updated Thu Jun 28 04:43:57 EDT 2007

gamma/X separation by energy

 

gamma/X separation by energy


Pibero Djawotho
Last updated Wed Jul 11 11:10:26 EDT 2007

gamma/X separation by energy with pT weights

 

gamma/X separation by energy with pT weights


Pibero Djawotho
Last updated Thu Jul 12 00:28:35 EDT 2007

gamma/X separation by energy with pT weights and normalized by number of events

 

gamma/X separation by energy with pT weights and normalized by number of events


Pibero Djawotho
Last updated Wed Jul 18 14:55:08 EDT 2007

gamma/pi0 separation efficiency and rejection at pT=5-7 GeV

 

gamma/pi0 separation efficiency and rejection at pT=5-7 GeV



Pibero Djawotho
Last updated Wed Jul 4 17:45:26 EDT 2007

gamma/pi0 separation efficiency and rejection at pT=9-11 GeV

 

gamma/pi0 separation efficiency and rejection at pT=9-11 GeV



Pibero Djawotho
Last updated Wed Jul 4 13:23:41 EDT 2007

gamma/pi0 separation efficiency and rejection at pT=9-11 GeV

 

gamma/pi0 separation efficiency and rejection at pT=9-11 GeV



Pibero Djawotho
Last updated Wed Jul 4 13:23:41 EDT 2007

2007.07.09 How to run the gamma fitter

 

How to run the gamma fitter


The gamma fitter runs out of the box. The code consists of the classes StGammaFitter and StGammaFitterResult in CVS. After checking out a copy of offline/StGammaMaker, cd into the offline directory and run:

root4star StRoot/StGammaMaker/macros/RunGammaFitterDemo.C

The following plots will be generated on the ROOT canvas and dumped into PNG files.


Pibero Djawotho
Last modified Mon Jul 9 18:40:07 EDT 2007

2007.07.25 Revised gamma/pi0 algorithm in 2006 p+p collisions at sqrt(s)=200 GeV

 

Revised gamma/pi0 algorithm in 2006 p+p collisions at sqrt(s)=200 GeV


Description

The class

StGammaFitter

computes the maximal sided residual of the SMD response in the u- and v-plane for gamma candidates. It is based on C++ code developed by Jason Webb from the original code by Les Bland who got the idea from CDF (?) The algorithm follows the steps below:

  1. The SMD response, which is SMD strips with hits in MeV, in each plane (U and V) is stored in histogram hU and hV.
  2. Fit functions fU and fV are created. The functional form of the SMD peak is a double-Gaussian with common mean and fixed widths. The widths were obtained by the SMD response of single photons from the EEMC slow simulator. As such, the only free parameters are the common mean and the total yield. The actual formula used is: [0]*(0.69*exp(-0.5*((x-[1])/0.87)**2)/(sqrt(2*pi)*0.87)+0.31*exp(-0.5*((x-[1])/3.3)**2)/(sqrt(2*pi)*3.3))
    • [0] = yield
    • [1] = mean
  3. The mean is fixed to the strip with maximum energy and the yield is adjusted so the height of the fit matches that of the mean.
  4. The residual for each side of the peak is calculated by subtracting the fit from the data (residual = data - fit) from 2 strips beyond the mean out to 40 strips.
  5. The maximal sided residual is the greater residual of each side.

Code

Candidates selection

  • 2006 p+p at 200 GeV dataset from Sivers analysis (from Jan Balewski)
    /star/institutions/iucf/balewski/prodOfficial06_muDst/
  • Gamma candidate from gamma maker: 3x3 clusters with pt > 5 GeV
  • No track pointing to cluster
  • Minimum of 3 SMD hits in each plane
  • Cuts from Jan & Naresh electron analysis:
    • Preshower 1 energy > 0.5 MeV
    • Preshower 2 energy > 2.0 MeV
    • Postshower energy < 0.5 MeV
  • The triggers caption in the PDF files shows the trigger id's satisfied by the event. A red trigger id is a L2-gamma trigger. I observe that generally the L2-gamma triggered event are a bit cleaner. Also shown is the pt and energy of the cluster.

Raw SMD response

  1. No additional cuts
  2. Pick only L2-gamma triggers
  3. Pick only L2-gamma triggers but no jet patch trigger
  4. Make isolation cut (see below)

The parameters of the isolation cut were suggested by Steve Vigor:

Hi Pibero,

  In general, I believe people have used smaller cone radii for isolation
cuts than for jet reconstruction (where the emphasis is on trying to
recover full jet energy).  So you might try something like requiring
that no more than 10 or 20% of the candidate cluster E_T appears
in scalar sum p_T for tracks and towers within a cone radius of
0.3 surrounding the gamma candidate centroid, excluding the
considered cluster energy.  The cluster may already contain energy
from other jet fragments, but that should be within the purview of
the gamma/pi0 discrimination algo to sort out.  For comparison, Les
used a cone radius of 0.26 for isolation cuts in his original simulations
of gamma/pi0 discrimination with the endcap.  Using much larger
cone radii may lead to accidental removal of too many valid gammas.


Steve


Pibero Djawotho
Last updated Wed Jul 25 10:07:07 EDT 2007

2007.09.12 Endcap Electrons

 

Endcap Electrons


This analysis is based on the work of Jan and Justin on SMD Profile Analysis for different TPC momenta. See here for a list of cuts. The original code used by Jan and Justin is here.

    • Transverse running

    • Analysis uses 64 out of 300 runs from 2006 pp transverse run
    • MuDst are located at:
      /star/institutions/iucf/balewski/prodOfficial06_muDst/
    • No trigger selection

    Figure 1: Number of tracks surviving each successive cut

    Figure 2a: Number of tracks per trigger id for all electron candidates. Most common trigger ids are:

    127652 eemc-jp0-etot-mb-L2jet EEMC JP > th0 (32, 4 GeV) and ETOT > TH (109, 14 GeV), minbias condition, L2 Jet algorithm, reading out slow detectors, transverse running
    127271 eemc-jp1-mb EEMC JP > th1 (49, 8 GeV) && mb, reading out slow detectors, transverse running
    127641 eemc-http-mb-l2gamma EEMC HT > th1 (12, 2.6 GeV, run < 7100052;13, 2.8 GeV, run >=7100052) and TP > TH1 (17, 3.8 GeV, run < 710052; 21, 4.7 GeV, run>=7100052 ), minbias condition, L2 Gamma algorithm, reading out slow detectors, L2 thresholds at 3.4, 5.4, transverse running
    127622 bemc-jp0-etot-mb-L2jet BEMC JP > th0 (42, 4 GeV) and ETOT > TH (109, 14 GeV), minbias condition, L2 Jet algorithm, reading out slow detectors, transverse running; L2jet thresholds at 8.0,3.6,3.3

    Figure 2b: Number of tracks per trigger id for all electron candidates for pT > 4 GeV. The dominant trigger ids become:

    127641 eemc-http-mb-l2gamma EEMC HT > th1 (12, 2.6 GeV, run < 7100052;13, 2.8 GeV, run >=7100052) and TP > TH1 (17, 3.8 GeV, run < 710052; 21, 4.7 GeV, run>=7100052 ), minbias condition, L2 Gamma algorithm, reading out slow detectors, L2 thresholds at 3.4, 5.4, transverse running
    127262 eemc-ht2-mb-emul EEMC HT > th2 (22, 5.0 GeV) && mb, reading out slow detectors, emulated in L2, transverse running, different threshold from 117262
    127271 eemc-jp1-mb EEMC JP > th1 (49, 8 GeV) && mb, reading out slow detectors, transverse running
    127652 eemc-jp0-etot-mb-L2jet EEMC JP > th0 (32, 4 GeV) and ETOT > TH (109, 14 GeV), minbias condition, L2 Jet algorithm, reading out slow detectors, transverse running

    Figure 3: pT distribution of tracks before E/p, dE/dx and pT cut

    Figure 4: pT distribution of electron candidates with pT > 4 GeV

    Figure 5: η distribution of electron candidates (all pT)

    Figure 6: φ distribution of electron candidates (all pT)

    Figure 7: dE/dx of tracks before E/p and dE/dx cuts (all pT)

    Figure 8: dE/dx of tracks before E/p and dE/dx cuts (pT > 4 GeV)

    Figure 9: dE/dx of tracks before E/p and dE/dx cuts (all pT and 0.8 < η < 1.0)

    Figure 10: dE/dx of tracks before E/p and dE/dx cuts (all pT and 1.0 < η < 1.2)

    Figure 11: dE/dx of tracks before E/p and dE/dx cuts (all pT and 1.2 < η < 1.4)

    Figure 12: dE/dx of tracks before E/p and dE/dx cuts (all pT and 1.4 < η < 1.6)

    Figure 13: dE/dx of tracks before E/p and dE/dx cuts (all pT and 1.6 < η < 1.8)

    Figure 14: dE/dx of tracks before E/p and dE/dx cuts (all pT and 1.8 < η < 2.0)

    • Click here for SMD profiles of transverse electron candidates.
    • Click here for ROOT file with transverse electrons ntuple.

    • Longitudinal running

    • MuDst are located at:
      /star/institutions/iucf/hew/2006ppLongRuns/
      

    Figure 2.1

    Figure 2.2: The dominant trigger ids are:

    137273 eemc-jp1-mb EEMC JP > th1 (52, 8.7 GeV) && mb, reading out slow detectors, longitudinal running 2
    137641 eemc-http-mb-l2gamma EEMC HT > th1 (16, 3.5 GeV) and TP > th1 (20, 4.5 GeV), minbias condition, L2 Gamma algorithm, reading out slow detectors, L2 thresholds at 3.7, 5.2, longitudinal running 2
    137262 eemc-ht2-mb-emul EEMC HT > th2 (22, 5.0 GeV) && mb, reading out slow detectors, emulated in L2, longitudinal running 2
    137222 bemc-jp1-mb BEMC JP > th1 (60, 8.3 GeV) && mb, reading out slow detectors, longitudinal running 2

    Figure 2.3a

    Figure 2.3

    Figure 2.4

    Figure 2.5

    Figure 2.6

    Figure 2.7

    Figure 2.8

    Figure 2.9

    Figure 2.10

    • Click here for SMD profiles of longitudinal electron candidates.
    • Click here for ROOT file with longitudinal electrons ntuple.

    • Code

    Click here for a tarball of the code used in this analysis.

    SMD response function

    • f(x)=p0*(0.69*exp(-0.5*((x-p1)/0.87)**2)/(sqrt(2*pi)*0.87)+0.31*exp(-0.5*((x-p1)/3.3)**2)/(sqrt(2*pi)*3.3))
      
    • p0 = yield
    • p1 = centroid

    Transverse

    21 electrons

    Longitudinal

    99 electrons


Pibero Djawotho
Last updated Wed Sep 12 08:29:53 EDT 2007

2008.01.23 Endcap etas

 

Endcap etas

Endcap etas

This analysis to look for etas at higher energy is in part motivated by this study. The interest in etas, of course, is that their decay photons are well separated at moderate energies (certainly more separated than the photons from pi0 decay). I ran Weihong's pi0 finder with tower seed threshold of 0.8 GeV and SMD seed threshold of 5 MeV (I believe his default SMD seed setting is 2 MeV). I then look in the 2-photon invariant mass region between 0.45 and 0.65 GeV (the PDG nominal mass for the eta is 0.54745 +/- 0.00019 GeV). I observe what looks like a faint eta peak. The dataset processed is the longitudinal 2 run of 2006 from the 20 runs sitting on the IUCF disk in Weihong's directory (/star/institutions/iucf/hew/2006ppLongRuns/).

Within the reconstructed mass window 0.45 to 0.65 GeV, I take a look at the decay photon shower profiles in the SMD. The samples are saved in the file etas.pdf. For the most part, these shower shapes are cleaner than the original sample. Although the statistics are not great.

Additional Material

Documents


Pibero Djawotho
Last updated Wed Jan 23 12:35:43 EST 2008

2008.02.27 ESMD shape library

 

ESMD shape library


Shower Widths for Monte Carlo and Data

Description

Hal did a comparison of the widths of the shower shapes between Monte Carlo and data. Below is a description of what was done.

      I took the nominal central value, either from the maxHit or the
nominal central value, and added the energy in the +/- 12 strips.  Then I
computed the mean strip (which may have been different from the nominal
central value!!).  I normalized the shape to give unit area for each smd
cluster, and added to the histograms separately for U and V and for MC and
data (= Will's events).  I did NOT handle Will's events correctly, just
using whatever event was chosen randomly, rather than going through his
list sequentially.  Note I ran 1000 events, and got 94 events in my shower
shape histos.

      So, there are several minor problems.  1) I didn't go through Will's
events sequentially.  2) I normalized, but perhaps not to the correct 25
strips, because the mean strip and the nominal strip may have differed.
3) there may have been a cutoff on some events due to being close to one
end of the smd plane (near strip 0 or 287).  My sense from looking at the
plots is that these don't matter much.

      The conclusion is that the MC shape is significantly narrower than
the shape from Will's events, which is obviously narrower than the random
clusters we were using at first with no selection for the etas.  Hence, we
are not wasting our time with this project.

Decsription of Pythia Sample

A few histograms were added to the code:

  • MC is Pythia gamma-jet at partonic pT 9-11 GeV with gamma in the Endcap
  • Data is from Will Jacobs golden events from Weihong sample
  • Require no conversion
  • Require all hits from direct photon in same sector


Figure 1:

Data vs. MC mean u-strip



Figure 2:

Data vs. MC mean v-strip



Figure 3:

Data vs. MC u-strip sigma



Figure 4:

Data vs. MC v-strip sigma



Figure 5:

MC E

v

vs. E

u

Figure 6:

Data E

v

vs. E

u

Figure 7:

MC energy asymmetry in SMD planes



Figure 8:

Data energy asymmetry in SMD planes



Figure 9:

Shower shape library index used (picked at random)

 

Single events shower shapes are displayed in

esmd.pdf

or

esmd_solid.pdf

.

  • green = projected position of direct photon in the Endcap
  • blue = Monte Carlo SMD response
  • red = Data SMD response

Hal Spinka
Pibero Djawotho
Last modified Wed Feb 27 09:51:27 EST 2008

2008.02.28 ESMD QA for run 7136033

 

ESMD QA for run 7136033



Pibero Djawotho
Last updated Thu Feb 28 16:17:55 EST 2008

2008.03.04 A second look at eta mesons in the STAR Endcap Calorimeter

 

A second look at eta mesons in the STAR Endcap Calorimeter


Introduction

In case you missed it, the first look is

here

. I processed

44 runs

from the 2006 pp longitudinal 2 runs and picked events tagged with the L2gamma trigger id (137641). I ran the StGammaMaker on the MuDst files from these runs and produced gamma trees. These gamma trees are available at

/star/institutions/iucf/pibero/2007/etaLong/

. Within the StGammaMaker framework, I developed code to seek candidate etas with emphasis on high purity. The macros and source files are:

Note, the workhorse function is

StEtaFinder::findTowerPoints()

.

Algorithm

  1. Find seed tower with pT > 0.8 GeV
  2. Require no TPC track into the seed tower
  3. Get the ranges of SMD U & V strips that span the volume of the seed tower
  4. Find the strips with maximum energy within these ranges
  5. Require that the maximum strips have more than 2 MeV in each SMD plane
  6. Get the intersection of the maximum strips and ensures that it lies within 70% of the fiducial volume of the seed tower
  7. Make sure the photon candidate responsible for the SMD clusters above enters and exits the same seed tower
  8. Form a 11-strip cluster in each plane with +/-5 strips around the max strip and require that it contains 70% of the energy in a range +/-20 strips around the max strip
  9. Require that the energy asymmetry between the 11-strip clusters in the U and V planes be less than 20%
  10. Create a point using the energy of the seed tower and the position of the intersection of the max strips in the SMD U and V planes
  11. Repeat until seed towers in the event are exhausted
  12. Combine different points in the event to calculate the invariant mass
  13. Diphoton pairs with invariant mass between 0.4 and 0.6 GeV are saved to a PDF file

Invariant mass

I fit the diphoton invariant mass with two Gaussians, one for the pi0 peak (p0-p2) and another one for the eta peak (p3-p5) plus a quadratic for the background (p6-p8). The Gaussian is of the form p0*exp(0.5*((x-p1)/p2)**2) and the quadratic is of the form p6*+p7*x+p8*x**2. A slightly better chi2/ndf in the fit is achieved by using Breit-Wigner functions instead of Gaussians for the signal here. I calculate the raw yield of etas from the fit as p3*sqrt(2*pi)*p5/bin_width = 85 where each bin is 0.010 GeV wide. I select candidate etas in the mass range 0.45 to 0.55 GeV and plot their photon response in the shower maximum detector here. Since we are interested in collecting photons of pT > 7 GeV, only those candidate photons with pT > 5 GeV will be used in the shower shape library. I also calculate the background under the signal region by integrating the background fit from 0.45 to 0.55 GeV and get 82 counts.

  • S = 85
  • B = 82
  • S:B = 1.03:1
  • S/√S+B = 6.6

Additional plots

 

2008.03.08 Adding the SMD energy to E_reco/E_MC for Photons

 

Adding the SMD energy to E_reco/E_MC for Photons

The following is a revisited study of E_reco/E_MC for photons with the addition of the SMD energy to E_reco.

QA plots for each energy

  1. 5 GeV
  2. 10 GeV
  3. 20 GeV
  4. 40 GeV
  5. 80 GeV
  6. 160 GeV

E_SMD/E_reco vs. eta



Pibero Djawotho
Last updated Thu Mar 8 04:27:28 EST 2007

2008.03.21 Chi square method

Chi square method

 

[IMG] SectorVsRunNumber.png   10-Feb-2010 12:22   14K  
[IMG] ShowerShapes.png        10-Feb-2010 12:22   17K  
[IMG] chiSquareMC.png         10-Feb-2010 12:22   13K  
[IMG] chiSquarePibero.png     10-Feb-2010 12:22   16K  
[IMG] chiSquareWill.png       10-Feb-2010 12:22   16K  
[IMG] chiSquareWillAndMC.png  10-Feb-2010 12:22   17K  

 

2008.04.08 Data-Driven Shower Shapes

 

Data-Driven Shower Shapes


Gamma Conversion before the Endcap

The plots below show the conversion process before the Endcap. I look at prompt photons heading towards the Endcap from a MC gamma-jet sample with a partonic pT of 9-11 GeV. I identify those photons that convert using the GEANT record. The top left plot shows the total number of direct photons and those that convert. I register a 16% conversion rate. This is consistent with Jason's 2006 SVT review. The top right plot shows the source of conversion, where most of the conversions emanate from the SVT support cone, also consistent with Jason's study. The bottom left plot shows the separation in the SMD between the projected location of the photon and the location of the electron/positron from conversion.

Shower shapes comparison

This

PDF

file shows several shower shapes in a single plot for comparison:

  • MC - Monte Carlo shower shape from the 9-11 GeV pT gamma-jet Pythia sample
  • DD - Data-driven Monte Carlo shower shape (Each final state photon shower shape is replaced with a corresponding shower shape from data in the same sector configuration, energy, preshower, and U/V-plane bin).
  • Standard MC - Monte Carlo shower shape parametrized by Hal (also from the 9-11 GeV pT gamma-jet Pythia sample)
  • Will - Data shower shape derived from photons from eta decays by Will using a modified version of Weihong/Jason meson pi0 finder
  • Pibero - Data shower shape derived from photons from eta decays by Pibero using a crude eta finder

Shower Shapes Sorted by SMD Plane, Sector Configuration, Energy and Preshower

These Shower Shapes are binned by:

  1. SMD plane (U and V)
  2. Sector configuration with the formula sector%3 where sector=1..12, so 3 different bins. More details can be found at the EEMC Web site under the Geometry link.
  3. Energy of the photon (E < 8 GeV and E > 8 GeV)
  4. Preshower energy (pre1==0&amp;&amp;pre2==0) and (pre1&gt;0||pre2&gt;0)

They are then fitted with a triple-Gaussian of the form:

[0]*([2]*exp(-0.5*((x-[1])/[3])**2)/(sqrt(2*pi)*[3])+[4]*exp(-0.5*((x-[1])/[5])**2)/(sqrt(2*pi)*[5])+(1-[2]-[4])*exp(-0.5*((x-[1])/[6])**2)/(sqrt(2*pi)*[6]))

Comparison of Sided Residuals for Monte Carlo (MC) and Data-Driven (DD) Shower Shapes

All fits to MC are with reference to the old Monte carlo fit function:

[0]*(0.69*exp(-0.5*((x-[1])/0.87)**2)/(sqrt(2*pi)*0.87)+0.31*exp(-0.5*((x-[1])/3.3)**2)/(sqrt(2*pi)*3.3))

All fits to the data are with reference to a single

Shower Shape

. The fit function is:

[0]*([2]*exp(-0.5*((x-[1])/[3])**2)/(sqrt(2*pi)*[3])+[4]*exp(-0.5*((x-[1])/[5])**2)/(sqrt(2*pi)*[5])+(1-[2]-[4])*exp(-0.5*((x-[1])/[6])**2)/(sqrt(2*pi)*[6]))

  1. All Shower Shapes
  2. No Conversion
  3. Conversion
  4. No Preshower
  5. Preshower
  6. No Conversion and Preshower
  7. Sector Configuration 0
  8. Sector Configuration 1
  9. Sector Configuration 2

Comparison of Sided Raw Tails for Monte Carlo (MC) and Data-Driven (DD) Shower Shapes

  1. All Shower Shapes
  2. No Conversion
  3. Conversion
  4. No Preshower
  5. Preshower
  6. No Conversion and Preshower
  7. Sector Configuration 0
  8. Sector Configuration 1
  9. Sector Configuration 2

Pibero Djawotho
Last updated Tue Apr 8 17:29:40 EDT 2008

2008.04.12 Data-Driven Residuals

 

Data-Driven Residuals


Gammas

Jets

Background Rejection vs. Signal Efficiency

Partonic pT=9-11 GeV Partonic pT=9-11 GeV

Background Rejection vs. Signal Efficiency (Neutral Meson pT > 8 GeV)


Pibero Djawotho
Last updated Sat Apr 12 13:27:50 EDT 2008

2008.04.12 Pythia Gamma-Jets

 

Pythia Gamma-Jets


Gamma-Jet Yields

During Run 6, the L2-gamma trigger (trigger id 137641) sampled 4717.10 nb-1 of integrated luminosity. By restricting the jet to the Barrel, |ηjet|<1, and the gamma to the Endcap, 1<ηgamma<2, the yield of gamma-jets is estimated as the product of the luminosity, the cross section, and the fraction of events in the phasespace above. The total cross section reported by Pythia for gamma-jet processes at different partonic pT thresholds is listed in the table below. No efficiencies are included.

pT threshold [GeV] Total cross section [mb] Fraction Ngamma-jets
5 6.551E-05 0.0992 30654
6 3.075E-05 0.1161 16840
7 1.567E-05 0.1150 8500
8 8.654E-06 0.1131 4617
9 4.971E-06 0.1223 2868
10 2.953E-06 0.1151 1603

Gamma-Jets pT slope

The pT slope is exp(-0.69*pT)=2^(-pT), so the statistics are halved with each 1 GeV increase in pT.

References

  1. Yield estimates based on single-particle MC sample, and comparison w/ pythia (Jason Webb)
  2. Pythia estimates of gamma-jet yields (Jim Sowinski)

Pibero Djawotho
Last updated Sat Apr 12 15:15:56 EDT 2008

2008.04.16 Jet Finder QA

 

Jet Finder QA

Pibero Djawotho
Last updated Wed Apr 16 08:33:01 EDT 2008

2008.04.20 BUR 2009

Partonic pT=7-9 GeV

Partonic pT=9-11 GeV

Combined Partonic pT

2008.04.22 Run 6 Photon Yield Per Trigger

 

Run 6 Photon Yield Per Trigger


Introduction

The purpose of this study is to estimate the photon yield per trigger in the Endcap Electromagnetic Calorimeter during Run 6. The trigger of interest is the L2-gamma trigger. Details of the STAR triggers during Run 6 were compiled in the 2006 p+p run (run 6) Trigger FAQ by Jamie Dunlop. The triggers relevant to this study are reproduced in the table below for convenience.

Trigger id Trigger name Description
117641 eemc-http-mb-l2gamma EEMC HT > th1 (12, 2.6 GeV) and TP > TH1 (17, 3.8 GeV), minbias condition, L2 Gamma algorithm, reading out slow detectors, L2 thresholds at 2.9, 4.5
127641 eemc-http-mb-l2gamma EEMC HT > th1 (12, 2.6 GeV, run < 7100052;13, 2.8 GeV, run >=7100052) and TP > TH1 (17, 3.8 GeV, run < 710052; 21, 4.7 GeV, run>=7100052 ), minbias condition, L2 Gamma algorithm, reading out slow detectors, L2 thresholds at 3.4, 5.4, transverse running
137641 eemc-http-mb-l2gamma EEMC HT > th1 (16, 3.5 GeV) and TP > th1 (20, 4.5 GeV), minbias condition, L2 Gamma algorithm, reading out slow detectors, L2 thresholds at 3.7, 5.2, longitudinal running 2

The luminosity sampled by each trigger was also caclulated here by Jamie Dunlop. The luminosity for the relevant triggers is reproduced in the table below for convenience. The figure-of-merit (FOM) is calculated as FOM=Luminosity*PB*PY for transverse runs and FOM=Luminosity*PB2*PY2 for longitudinal runs where PB is the polarization of the blue beam and PY is the polarization of the yellow beam. Naturally, in spin physics, the FOM is the better indicator of statistical precisison.

Trigger First run Last run Luminosity [nb-1] Figure-of-merit [nb-1]
117641 7093102 7096017 118.88 11.89
127641 7097009 7129065 3219.04 1099.43
137641 7135050 7156028 4717.10 687.65

Event selection

Trigger selection

For this study, only the trigger of longitudinal running 2 (137641) is used. As mentioned above, at level-0, an EEMC high tower above 3.5 GeV and its associated trigger patch above 4.5 GeV in transverse energy coupled with a minimum bias condition, which is simply a BBC coincidence to ensure a valid collision, is required for the trigger to fire. The EEMC has trigger patches of variable sizes depending on their location in pseudorapidity. (The BEMC has trigger patches of fixed sizes, 4x4 towers.) At level-2, a high tower above 3.7 GeV and a 3x3 patch above 5.2 GeV in transverse energy is required to accept the event.

Gamma candidates

In addition to selecting events that were tagged online by the L2-gamma trigger, the offline

StGammaMaker

looks for tower clusters with minimum transverse energy of 5 GeV. These clusters along with their associated TPC tracks, preshower and postshower tiles, and SMD strips form gamma candidates. Gamma trees for the 2006 trigger ID 137641 with primary vertex are located at

/star/institutions/iucf/pibero/2006/gammaTrees/

.

Track isolation

The gamma candidate is required to have no track pointing to any of its towers.

EMC isolation

The gamma candidate is required to have 85% of the total transverse energy in a cone of radius 0.3 in eta-phi space around the position of the gamma candidate. That is E

Tgamma

/E

Tcone

> 0.85 and R=√Δη

2

+Δφ

2

=0.3 is the cone radius.

Jet Reconstruction

The gamma candidate is matched to the best away-side jet with neutral fraction < 0.9 and cos(φ

gamma

jet

) < -0.8. The 2006 jet trees are produced by Murad Sarsour at PDSF in

/eliza13/starprod/jetTrees/2006/trees/

. A local mirror exists at RCF under the directory

/star/institutions/iucf/pibero/2006/jetTrees/

.

Spin Information

Jan Balewski has an excellent write-up, Offline spin DB at STAR, on how to get spin states. I obtain the spin states from the skim trees in the jet trees directory. In brief, the useful spin states are:

Blue Beam Polarization Yellow Beam Polarization Spin4
P P 5
P N 6
N P 9
N N 10

Event Summary

L2-gamma triggers 730128
Endcap gamma candidates 723848
Track isolation 246670
EMC isolation 225400
Away-side jet 99652
SMD max sided residual 19281
Barrel-only jet 15638

Note the number of L2-gamma triggers include only those events with a primary vertex and at least one gamma candidate (BEMC or EEMC).

Gamma-Jet Plots

 
 

Comparison of pT Slope with Pythia

Partonic Kinematics Reconstruction

Open Questions

  1. I count ~2.4M events with trigger id 137641 using the Run 6 Browser, however my analysis only registers about ~0.78M.

Pibero Djawotho
Last updated Tue Apr 22 11:40:18 EDT 2008

2008.05.07 Number of Jets

 

Number of Jets


After selecting Endcap gamma candidates out of L2-gamma triggers, applying track and EMC isolation cuts, and matching the Endcap gamma candidate to an away-side jet, I record the number of jets below per event. Surprisingly, 8% of the events only have 1 jet. Those are events where the Endcap gamma candidate was not reconstructed as a neutral jet by the jet finder. The question is why.

I display both Barrel and Endcap calorimeter towers (the z-axis represents tower energy) and draw a circle of radius 0.3 around the gamma candidate and a circle of radius 0.7 around the away-side jet for 2006 pp200 run 7136022. Even though many of the gamma candidates not reconstructed by the jet finder are at the forward edge of the Endcap, it is not at all clear why those that are well within the detector are not being reconstructed.


Pibero Djawotho
Last updated Wed May 7 09:54:32 EDT 2008

2008.05.09 Gamma-jets pT distributions

 

Gamma-jets pT distributions


Note:

No cuts on residuals applied.

Not cut on number of towers in gamma cluster

Number of towers in gamma cluster <= 9

Number of towers in gamma cluster <= 4

Number of towers per cluster distributions

Gamma candidates xy-distribution

z-vertex distribution

Eta distribution

Phi distribution

log10(E_post/E_tow) distribution

pT asymmetry

References

  1. Ilya's pT distributions
  2. Michael's weigthing of simulation

Pibero Djawotho
Last updated Fri May 9 08:19:00 EDT 2008

2008.05.19 Binning the shower shape library

 

Binning the shower shape library


Distributions

Shower Shapes


Pibero Djawotho
Last updated Mon May 19 12:09:48 EDT 2008

2008.06.03 Jet A_LL Systematics

 

Jet A_LL Systematics


Hypernews discussion

jet A_LL systematic possibility

References

  1. I.P. Auer et al, Phys.Rev.D 32(1985)1609
  2. J. Bystricky et al, J.Phys. France 39(1978)1

Pibero Djawotho
Last updated Tue Jun 3 15:35:24 EDT 2008

2008.06.18 Photon-jet reconstruction with the EEMC - Part 2 (STAR Collaboration Meeting - UC Davis)

2008.07.16 Extracting A_LL and DeltaG

 

Extracting A_LL and DeltaG


Determining state of beam polarization for Monte Carlo events

While Pythia does a pretty good job of simulating prompt photon production in p+p collisions, it does not include polarization for the colliding protons nor partons. A statistical method for assigning polarization states for each event based on ALL [1] is demonstrated in this section. For an average number of interactions for each unpolarized bunch crossing, Neff, the occurence of an event with a particular polarization state obeys a Poisson distribution with average yield of events per bunch crossing:

For simplicity, the polarizations of the blue and yellow beams are assumed to be P

B

=P

Y

=0.7 and N

eff

=0.01. The "+" spin state defines the case where both beams have the same helicities and the "-" spin state for the case of opposite helicities. The asymmetry A

LL

is calculated from the initial states polarized and unpolarized parton distribution functions and parton-level asymmetry:

The algorithm then consists in alternatively drawing a random value N

int

from the Poisson distributions with mean μ

+

and μ

-

until N

int

>0 at which point an interaction has occured and the event is assigned the current spin state. The functioning of the algorithm is illustrated in Figure 1a where an input A

LL

=0.2 was fixed and N

trials

=500 different asymmetries were calculated. Each trial integrated N

total

=300 events. It is then expected that the mean A

LL

~0.2 and the statistical precision~0.1:

Indeed, both the A

LL

and its error are reproduced. In addition, variations on the number of events per trial were investigated (N

total

) in Figure 1b. The extracted width of the Gaussian distribution for A

LL

is consistent with the prediction for the error (red curve).

  • ROOT macro used to generate Figure 1a SimALL.C
  • ROOT macro used to generate Figure 1b SimALL2.C
Figure 1a Figure 1b

Event reconstruction

For this study, the gamma-jets Monte Carlo sample for all partonic pT were used. As an example, the prompt photon processes for the partonic pT bin 9-11 GeV and their total cross sections are listed in the table below. Each partonic pT bin was divided into 15 files each of 2000 events.

 ==============================================================================
 I                                  I                            I            I
 I            Subprocess            I      Number of points      I    Sigma   I
 I                                  I                            I            I
 I----------------------------------I----------------------------I    (mb)    I
 I                                  I                            I            I
 I N:o Type                         I    Generated         Tried I            I
 I                                  I                            I            I
 ==============================================================================
 I                                  I                            I            I
 I   0 All included subprocesses    I         2000          9365 I  3.074E-06 I
 I  14 f + fbar -> g + gamma        I          331          1337 I  4.930E-07 I
 I  18 f + fbar -> gamma + gamma    I            2             8 I  1.941E-09 I
 I  29 f + g -> f + gamma           I         1667          8019 I  2.579E-06 I
 I 114 g + g -> gamma + gamma       I            0             1 I  1.191E-10 I
 I 115 g + g -> g + gamma           I            0             0 I  0.000E+00 I
 I                                  I                            I            I
 ==============================================================================

The cross sections for the different partonic pT bins has been tabulated by Michael Betancourt and is reproduced here for convenience.

Partonic pT [GeV] Cross Section [mb]
3-4 0.0002962
4-5 0.0000891
5-7 0.0000494
7-9 0.0000110
9-11 0.00000314
11-15 0.00000149
15-25 0.000000317
25-35 0.00000000990
35-45 0.000000000449

These events were processed through the 2006 pp200 analysis chain, albeit without any cuts on the SMD. The simulated quantities were taken from the Pythia record and the reconstructed ones from the analysis.

Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9

Partonic kinematics reconstruction

PartonicKinematics.C
Figure 10
Figure 11
Figure 12
Figure 13
Figure 14
Figure 15 (a)
Figure 15 (b): quark from proton 1 (blue beam, +z direction)
Figure 15 (c): quark from proton 1 (blue beam, +z direction) and q + g -> q + gamma subprocess (29)
Figure 15 (d): quark from proton 1 (blue beam, +z direction) and q + qbar -> gamma + g subprocess (14)

Predictions for A_LL and direct determination of DeltaG(x)

DeltaG.C
Figure 16 (a)
Figure 16 (b): quark from proton 1 (blue beam, +z direction)
Figure 16 (c): quark from proton 1 (blue beam, +z direction) and q + g -> q + gamma subprocess (29)
Figure 16 (d): quark from proton 1 (blue beam, +z direction) and q + qbar -> gamma + g subprocess (14)

References

  1. Appendix Simulation Studies of Direct Photon Production at STAR
  2. DeltaG(x,mu^2) from jet and prompt photon production at RHIC arXiv:hep-ph/0005320

Pibero Djawotho
Last updated Wed Jul 16 10:29:22 EDT 2008

2008.07.20 How to install Pythia 6 and 8 on your laptop?

 

How to install Pythia 6 and 8 on your laptop?


    • Install Pythia 6 and build the interface to ROOT

    Download the file pythia6.tar.gz from the ROOT site ftp://root.cern.ch/root/pythia6.tar.gz and unpack.
    tar zxvf pythia6.tar.gz
    
    A directory pythia6/ will be created and some files unpacked into it. Cd into it and compile the Pythia 6 interface to ROOT.
    cd pythia6/
    ./makePythia6.linux
    
    For more information, consult Installing ROOT from Source and skip to the section Pythia Event Generators.

    • Install Pythia 8

    Download the latest version of Pythia from http://home.thep.lu.se/~torbjorn/Pythia.html and unpack.
    tar zxvf pythia8108.tgz
    
    A directory pythia8108/ will be created. Cd into it and follow the instructions in the README file to build Pythia 8. Set the environment variables PYTHIA8 and PYTHIA8DATA (preferably in /etc/profile.d/pythia8.sh):
    export PYTHIA8=$HOME/pythia8108
    export PYTHIA8DATA=$PYTHIA8/xmldoc
    
    Run configure with the option for shared-library creation turned on.
    ./configure --enable-shared
    make
    

    • Install ROOT from source

    Download the source code for ROOT from http://root.cern.ch/ and compile.
    tar zxvf root_v5.20.00.source.tar.gz
    cd root/
    ./configure linux --with-pythia6-libdir=$HOME/pythia6 \
      --enable-pythia8 \
      --with-pythia8-incdir=$PYTHIA8/include \
      --with-pythia8-libdir=$PYTHIA8/lib
    make
    make install
    
    Set the following environment variables (preferably in /etc/profile.d/root.sh):
    export ROOTSYS=/usr/local/root
    export PATH=$PATH:$ROOTSYS/bin
    export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ROOTSYS/lib:/usr/local/pythia6
    export MANPATH=$MANPATH:$ROOTSYS/man
    
    You should be good to go. Try running the following Pythia 6 and 8 sample macros:
    root $ROOTSYS/tutorial/pythia/pythiaExample.C
    root $ROOTSYS/tutorial/pythia/pythia8.C
    

Pibero Djawotho
Last updated on Sun Jul 20 23:35:39 EDT 2008

2008.07.23 Hot Strips Identified by Hal Spinka

 

Hot Strips Identified by Hal Spinka


    • Run 7136034 Sector 8

    Strips 08U020, 08U080, 08V185 and 08V225

    • Run 7137036 Sector 9

    Strips 09V064


    Pibero Djawotho
    Last updated Wed Jul 23 03:40:54 EDT 2008

2008.07.24 Strips from Weihong's 2006 ppLong 20 runs

 

Strips from Weihong's 2006 ppLong 20 runs


Energy [GeV] vs. strip id

2006ppLongRuns.pdf

Raw ADC vs. strip id

7136022.pdf 7136033.pdf 7136034.pdf 7137036.pdf 7138001.pdf 7138010.pdf 7138032.pdf 7140046.pdf 7143012.pdf 7144014.pdf 7145018.pdf 7145024.pdf 7146020.pdf 7146077.pdf 7147052.pdf 7148027.pdf 7149005.pdf 7152062.pdf 7153008.pdf 7155052.pdf


Pibero Djawotho
Last updated Thu Jul 24 10:35:50 EDT 2008

G/h Discrimination Algorithm (Willie)

My blog pages, from first to last:

01/25: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/jan/25/photon-analysis-progress-week-1-21-08-1-25-08.  This post discusses the problem with the spike in secondary tracks at eta=1 in our single-particle simulations.

01/28: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/jan/28/further-qa-plots.  This post has QA plots for every particle sample Ross generated, both in the barrel and in the endcap.

02/01: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/01/more-qa-plots-time-efficiencies.  This post has QA plots for gamma and piminus (barrel and endcap) as well as reconstruction efficiencies.

02/04: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/04/photon-qa-efficiency-plots-error-bars.  This post adds error bars to the reconstruction efficiencies for the photon barrel sample.

02/05: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/05/first-clustering-plots.  This post has the first clustering plots, for muons and gammas (barrel only), showing cluster energy, energy-weighted cluster eta and phi, and the number of seeds and clusters passing the thresholds for each event.

02/12: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/12/preshower-plots.  This post has preshower plots from the gamma barrel sample, but the plots are of all preshowers in the event and use the preshower information generated by the BEMC simulator and so are not useful.

02/13: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/13/more-clustering-plots.  This post has geant QA plots combined with the clustering plots from 02/05 above, but for the gamma and piminus barrel samples.

02/19: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/19/cluster-track-matching-plots.  This post investigates the cluster-to-track matching for the gamma barrel sample, using a simple distance variable d=sqrt((delta eta)^2+(delta phi)^2)) to match clusters to tracks and plotting the resulting energy distributions, the energy ratio, etc.

02/21: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/21/more-preshower-plots.  This post plots preshower distributions but uses the preshower information from the BEMC simulator and so is not useful.

02/28: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/feb/28/further-preshower-plots-not-completed-yet.  Figures 1, 3, and 5 in this post plot the geant preshower energy deposition for gammas, piminuses, and muons (Figs 2, 4, and 6 plot reconstructed preshower information again and so are not useful).

03/04: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/mar/04/muon-preshower-plots.  This post expands on the post of 02/28, with additional plots using the geant preshower information, including preshower cluster energy vs. tower cluster energy.

03/06: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/mar/06/first-physics-cuts.  This post basically recaps the previous post and adds a cut: unfortunately the cut is based partly on the thrown particle energy and so is not useful.

03/18: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/mar/18/smd-qa-plots.  This post plots energy-weighted SMD phi and eta distributions, as well as the total energy deposited in the BSMDE and BSMDP strips located behind a cluster.

03/28: http://drupal.star.bnl.gov/STAR/blog-entry/wleight/2008/mar/28/smd-clustering-plots.  This post contains SMD clustering plots for barrel gamma and piminus samples.

Neutral Pions 2005: Frank Simon

Information about the 2005 Spin analysis (focused on A_LL and <z>, some QA plots for cross section comparisons) will be archived here. The goal is obviously the 2005 Pi0 spin paper.

Invariant Mass and Width: Data-MC

Here I show the invariant masses and corresponding widths I obtain using my cross section binning. These are compared to MC values.

The Method:

  • Invariant mass Data histograms (low mass background and combinatoric background subtracted) are fitted with a gaussian in the range 0.1 - 0.18 GeV/c^2. This gives the mass (gaussian mean) and width (gaussian sigma)
  • MC invariant mass histograms are obtained from correctly associated MC Pi0s after reconstruction. No weighting of the different partonic pt samples is performed. This can (and will) introduce a bias
    • Then the same fitting procedure as for data is applied

The results are shown in the two figures below.

Mass:

 

Width:

 

 

 

Neutral Pion Paper: 2005 ALL & <z>

Neutral Pion Paper for 2005 data: Final Results.

There are two spin plots planned for the paper, one with the 2005 A_LL and one with the <z>. In addition to this the cross section will be included (analysis by Oleksandr used for publication).

 

Final result for A_LL:

 

Figure 1: Double longitudinal spin asymmetry for inclusive Pi0 production. The curves show predictions from NLO pQCD calculations based on the gluon distributions from the GRSV, GS-C and DSSV global analyses. The systematic error shown by the gray band does not include a 9.4% normalization uncertainty due to the polarization measurement.

 

The chi2/ndf for the different model curves are:

GRSV Std: 0.740636
GRSV Max: 3.49163
GRSV Min: 0.94873
GRSV Zero: 0.546512
GSC: 0.513751
DSSV: 0.543775

 

 

Final Result for <z>:

Figure 2: Mean momentum fraction of Pi0s in their associated jet as a function of p_T for electromagnetically triggered events. The data points are plotted at the bin center in pion p_T and are not corrected for acceptance or trigger effects. Systematic errors, estimated from a variation of the cuts, are shown by the grey band underneath the data points. The lines are results from simulations with the PYTHIA event generator. The solid line includes detector effects simulated by GEANT, while the dotted line uses jet finding on the PYTHIA particle level. The inset shows the distribution of pT, π / pT, Jet for one of the bins, together with a comparison to PYTHIA with a full detector response simulation.

 

Below are links to details about the two results.

 

<z> Details

<z> Details

 

The goal of this analysis is to relate the neutral pions to the jets they are embedded in. The analysis is done using the common spin analysis trees, which provide the necessary tools to combine the jet and neutral pion analysis.

A neutral pion is associated to a parent jet if it is within the jet cone of 0.4 in eta and phi. To avoid edge effects in the detector, only neutral pions with 0.3 < eta < 0.7 are accepted. 

 

Cut details:

E_neutral / E_total < 0.95

higher energy photon of Pi0 > 2.8 GeV (HT1 trigger); > 3.6 GeV (HT2 trigger)

combination HT1/HT2: below 5.7 GeV only HT1 is used, above that both HT1 and HT2 are accepted

 

The final result uses both HT1 and HT2 triggers, but a trigger separated study has also been done, as shown below. There, HT2 includes only those HT2 triggers that do not satisfy HT1 (because of prescale).

Figure 1: <z> for Pi0 in jets as a function of p_T for HT1 and HT2 triggers. Also shown is the mean jet p_T as a function of pion p_T.

 

Bin-by-Bin momentum ratio

Figure 2: Bin-by-bin ratio of pion to jet p_T. The <z> is taken from the mean of these distributions, the error is the error on the mean. A small fraction of all entries have higher Pi0 p_T than jet p_T. Similar behavior is also observed for Pythia MC with GEANT jets. This obviously increases the <z>. An alternative would be to reject those events. The agreement with MC becomes worse if this is done.

 

Here is the data - MC comparison for 3 of the above bins. For the simulation, the reconstruction of the Pi0 is not required to keep statistics reasonable, so the true Pi0 pt is used. However, the MC jet finding uses all momenta after Geant, this is why the edges are "smoother" in the MC plot than in the data plots. Since <z> is an average value, this is not expected to be affected by this, since on average the Pi0 pt is reconstructed right.

Figure 3: Data / MC for Bin 5: 6.7 to 8 GeV

Figure 4: Data / MC for Bin 6: 8 to 10 GeV

Figure 5: Data / MC for Bin 7: 10 to 12 GeV

 

 

 

 

A_LL Details

Details on the A_LL result and the systematic studies:

The result in numbers:

Bin <p_T> [GeV] in bin A_LL stat. error syst. error
1 4.17 0.01829 0.03358 0.01603
2 5.41 -0.01913 0.02310 0.01114
3 7.06 0.00915 0.03436 0.01343
4 9.22 -0.06381 0.06366 0.01862

 

A_LL as separated by trigger:

Figure 1: A_LL as a function of p_T for HT1 (black) and HT2 (red) triggers separately. HT1 here is taken as all triggers that satisfy the HT1 requirement, but not HT2. Since the HT2 prescale is one, there are very little statistics for HT1 at the highest p_T. The highest p_T point for HT1 is outside the range of the plot, and has a large error bar. The high p_T HT1 data is used in the combined result. 

 

Systematics: Summary

 

  Bin 1 Bin 2 Bin 3 Bin4
relative luminosity 0.0009 0.0009 0.0009 0.0009
non-longitudinal pol. 0.0003 0.0003 0.0003 0.0003
beam background 0.0012 0.0084 0.0040 0.0093
yield extraction 0.0144 0.0044 0.0102 0.0116
invariant mass background 0.0077 0.0061 0.0080 0.0108
total 0.01603 0.01114 0.01343 0.01862

The first two systematics are common to all spin analyses. The numbers here are taken from the jet analysis. No Pi0 non-longitudinal analysis has been performed due to lacking statistics. These systematics are irrelevant compared to the others.

The analysis specific systematics are determined from the data, and as such are limited by statistics. The real systematic limit of a Pi0 analysis with a very large data sit will be much lower.

For the yield extraction systematic the invariant mass cuts for the pion yield extraction are varied. The systematic is derived from the maximum change in asymmetry with changing cuts.

For the beam background, the systematic is derived by studying how much A_LL changes when the beam background is removed. This is a conservative estimate that covers the scenario that only half of the background is actually removed. The asymmetry of the background events is consistent with zero.

For the invariant mass background systematic, A_LL is extracted in three invariant mass bins outside the signal region. The amount of background under the invariant mass peak (includes combinatorics, low mass and others) is estimated from the invariant mass distribution as shown below. For all three bins, the background A_LL is consistent with zero, a "worst case" of value + 1 sigma is assumed as deviation from the signal A_LL.

Invariant mass distribution:

Figure 2: Invariant mass distribution for HT1 events, second p_T bin. The red lines are the MC expectations for Pi0 and Eta, the green line is low mass background, the magenta line is combinatoric background, the thick blue line is a pol2 expectation for the other background, the blue thinner line is the total enveloppe of all contributions, compared to the data. At low mass, the background is overestimated.

 

Other systematic studies: False Asymmetries

 

False asymmetries (parity-violating single spin asymmetries) were studied to exclude systematic problems with spin asignments and the like. Of course the absence of problems in the jet analysis with the same data set makes any issues very unlikely, since jet statistics allow much better verifications than Pi0s. Still, single spin asymmetries were studied, and no significant asymmetries were observed. For both triggers, both asymmetries (yellow and blue) and for all p_T bins the asymmetries are consistent with zero, in most cases within one sigma of zero. So there are no indications for systematic effects. The single spin asymmetries are shown below:

Figure 3: Single spin asymmetry epsilon_L for the blue beam.

Figure 4: Single spin asymmetry epsilon_L for the yellow beam.

Neutral strange particle transverse asymmetries (tpb)

Neutral strange particle transverse asymmetry analysis

Here is information regarding my analysis of transverse asymmetries in neutral strange particles using 2006 p + p TPC data. This follows-on from and expands upon the earlier analysis I did, which can still be found at star.bnl.gov/protected/strange/tpb/analysis/. Comments, questions, things-you'd-like-to-see-done and so forth are welcomed. I'll catalogue updates in my blog as I make them.

The links listed below are in 'analysis-order'; best to use these for navigation rather than the alphabetically listed links Drupal links below/in the sidebar.

  1. Data used
  2. V0 decays
  3. Energy loss particle identification
  4. Geometrical cuts
  5. Single spin asymmetry with cross formula
  6. SSA using relative luminosity
  7. Double spin asymmetry

e-mail me at tpb@np.ph.bham.ac.uk




Data used

Data used in analysis

Data used for this analysis is 2006 p+p 200 GeV data taken with transverse polarisation, trigger setup "ppProductionTrans". This spanned days 97 (7th April) to 129 (9th May) inclusive. Trigger bemc-jp0-etot-mb-l2jet (ID 127622) is used. A file catalogue query with the following conditions gives a list of runs for which data is available:

trgsetupname=ppProductionTrans,tpc=1,year=2006,sanity=1,collision=pp200,
magscale=FullField,filename~physics,library=SL06e,production=P06ie

This generates a list of 549 runs. These runs are then compared against the spin PWG run QC (see http://www.star.bnl.gov/protected/spin/sowinski/runQC_2006) and are rejected if any of the following conditions are true:

  • The run is marked as unusable
  • The run has a jet patch trigger problem
  • The run has a spin bits problem
  • The run is unchecked

This excludes 172 runs, leaving 377 runs to be analysed.

I use a Maker class to create TTrees of event objects with V0 and spin information for these runs. Code for the Maker and Event classes can be found at /star/u/tpb/StRoot/StTSAEventMaker/ and /star/u/tpb/StRoot/StV0NanoDst/ respectively. Events are accepted only if they fulfill the following criteria:

  • Event contains specified trigger ID
  • StSpinDbMaker::isMaskedUsingBx48() returns false
  • StSpinDbMaker::offsetBX48minusBX7() returns zero

TTrees are produced for 358 runs (19 produce no/empty output), yielding 2,743,396 events.

The vertex distribution of events from each run are then checked by spin bits. A Kolmogorov test (using ROOT TH1::KolmogorovTest) is used to compare the vertex distributions for (4-bit) spin bits values 5, 6, 9 and 10. If any of the distributions are inconsistent, the run is rejected. Each run's mean event vertex z position is then plotted. Figure 1 shows the distribution, fitted with a Gaussian. A 3σ cut is applied and outlier runs rejected. 38 runs are rejected by these further cuts. The remaining 320 runs, spanning 33 RHIC fills and comprising 2,500,421 events, are used in the analysis.

Run-wise mean event vertex z distribution. It is well fitted by a Gaussian distribution.
Figure 1: Mean event vertex z for each run. The red lines indicate the 3σ cut.



Double spin asymmetry

Double spin asymmetry

I measure a double spin asymmetry defined as follows

A_TT=[N(parallel)-N(antiparallel)]/[N(parallel)+N(antiparallel)]
Equation 1

where N-(anti)parallel indicates yields measured in one half of the detector when the beam polarisations are aligned (opposite) and P1 and P2 are the polarisations of the beams. Accounting for the relative luminosity, these yields are given by

N(parallel)=N(upUp)/R4+N(downDown)
Equation 2
N(antiparallel)=N(upDown)/R5+N(downUp)/R6
Equation 2

where the arrows again indicate beam polarisations. Figures one and two show the fill-by-fill measurement of ATT, corrected by the beam polarisation, summed over all pT.

Straight-line fit to fill-by-fill measurement of K0s A_TT
Figure 1: K0S ATT fill-by-fill
Straight-line fit to fill-by-fill measurement of Lambda A_TT
Figure 2: Λ ATT fill-by-fill



Energy loss identification

Energy loss particle identification

The Bethe-Bloch equation can be used to predict charged particle energy loss. Hans Bichsel's model adds to this and the Bichsel function predictions for particle energy loss are compared with measured values. Tracks with dE/dx sufficiently far from the predicted value are rejected. e.g. when selecting for Λ hyperons, the positive track is required to have dE/dx consistent with that of a proton, and the negative track consistent with that of a π-minus.

The quantity σ = sqrt(N) x log( measured dE/dx - model dE/dx ) / R is used to quantify the deviation of the measured dE/dx from the model value. N is the number of track hits used in dE/dx determination and R is a resolution factor. A cut of |σ| < 3 applied to both V0 daughter tracks was found to significantly reduce the background with no loss of signal. Figures one to three below show the invariant mass distriubtions of the V0 candidates accepted and rejected and table one summarises the results of the cut. Background rejection is more successful for (anti-)Λ than for K0S because most background tracks are pions; the selection of an (anti-)proton daughter rejects the majority of the background tracks.


Invariant mass spectrum of V0 candidates passing K0s dE/dx cut
Figure 1a: Invariant mass spectrum of V0 candidates under K0s hypothesis passing dE/dx cut
Invariant mass spectrum of V0 candidates failing K0s dE/dx cut
Figure 1b: Invariant mass spectrum of V0 candidates under K0s hypothesis failing dE/dx cut
Invariant mass spectrum of V0 candidates passing Lambda dE/dx cut
Figure 2a: Invariant mass spectrum of V0 candidates under Λ hypothesis passing dE/dx cut
Invariant mass spectrum of V0 candidates failing Lambda dE/dx cut
Figure 2b: Invariant mass spectrum of V0 candidates under Λ hypothesis failing dE/dx cut
Invariant mass spectrum of V0 candidates passing anti-Lambda dE/dx cut
Figure 3a: Invariant mass spectrum of V0 candidates under anti-Λ hypothesis passing dE/dx cut
Invariant mass spectrum of V0 candidates failing anti-Lambda dE/dx cut
Figure 3b: Invariant mass spectrum of V0 candidates under anti-Λ hypothesis failing dE/dx cut


Species Pass (millions) Fail (millions) % pass
K0S 95.5 48.9 66.2 %
Λ 32.5 111.9 22.5 %
anti-Λ 11.8 132.5 8.2 %

Table 1




Geometrical cuts

Geometrical cuts

Energy loss cuts are successful in eliminating a significant portion of the background, but further reduction is required to give a clear signal. In addition final yields are calculated by a bin counting method, which requires that the background around the signal peak has a straight line shape. Therefore additional cuts are placed on the V0 candidates based on the geometrical properties of the decay. There are five quantities on which I chose to cut:

  • Distance of closest approach (DCA) of the V0 candidate to the primary vertex: if the V0 candidate is a genuine particle, its momentum vector should track back to the interaction point. Spurious candidates will not necessarily do so, therefore an upper limit is placed on the approach distance of the V0 to the interaction point.
  • DCA between the daughter tracks: due to detector resolution the daughter tracks never precisely meet, but placing an upper limit of the minimum distance of approach reduces background from spurious track crossings.
  • DCAs of the positive and negative daughter tracks to the primary vertex: the daughter tracks are curved due to the magnetic field and a neutral strange particle will decay some distance from the interaction point. Therefore the daughter tracks should not extrapolate back to the primary vertex, but to some distance away from it. Placing a lower limit on this distance can reduce background from tracks originating from the interaction point.
  • V0 decay distance: neutral strange particles decay weakly, with cτ ~ cm, so the decay vertex should typically be displaced from the interaction point. A lower limit placed on the decay distance of the V0 helps eliminate backgrounds from particles originating at the interaction point.

I wrote a class to help perform tuning of these geometrical cut quantities (see /star/u/tpb/StRoot/StV0CutTuning/) by a "brute force" approach; different permutations of the above quantities were attempted, and the resulting mass spectra analysed to see which permutations gave the best balance of background reduction and signal retention. In addition, the consistency of the background to a straight-line shape was required. Due to the limits on statistics, signal retention was considered a greater priority than background reduction. The cut values I decided upon are summarised in table one. Figures one to three show the resulting mass spectra (data are from all runs). Yields are calculated from the integral of bins in the signal (red) region minus the integrals of bins in the background (green) regions. Poisson (√N) errors are used. The background regions are fitted with a straight line, skipping the intervening bins. The signal to background quoted is the ratio of the maximum bin content to the value of the background fit evaluated at that mass. Note that the spectra have the the dE/dx cut included in addition to the geometrical cuts.

Species Max DCA V0 to PV* Max DCA between daughters Min DCA + daughter to PV Min DCA − daughter to PV Min V0 decay distance
K0S 1.0 1.2** 0.5 0.0** 2.0**
Λ 1.5 1.0 0.0** 0.0** 3.0
anti-Λ 2.0** 1.0 0.0** 0.0** 3.0

Table 1: Summary of geometical cuts. All cut values are in centimetres.

* primary vertex
** default cut present in micro-DST


Final K0s invariant mass specturm for all data with all cuts applied
Figure 1: Final K0S mass spectrum with all cuts applied.
Final Lambda invariant mass specturm for all data with all cuts applied
Figure 2: Final Λ mass spectrum with all cuts applied.
Final anti-Lambda invariant mass specturm for all data with all cuts applied
Figure 3: Final anti-Λ mass spectrum with all cuts applied.



Single spin asymmetry using cross formula

Single Spin asymmetry using cross formula

Equation one shows the cross-formula used to calculate the single spin asymmetry.

AP=[sqrt(N(L,up)N(R,down))-sqrt(N(L,down)N(R,up))]/[sqrt(N(L,up)N(R,down))+sqrt(N(L,down)N(R,up))]
Equation 1

where N is a particle yield, L(eft) and R(ight) indicate the side of the polarised beam to which the particle is produced and arrows indicate the polarisation direction of the beam. Equation one cancels acceptance and beam luminosity and allows simply the raw yields to be used for the calculation. The asymmetry can be calculated twice; once for each beam, summing over the polarisation states of the other beam to leave it "unpolarised". I previously used only particles produced at forward η when calculating the blue beam asymmetry, and backward η for yellow, but I now sum over the full η range for each. Equations two and three give the numbers for up/down polarisation for blue (westward at STAR) and yellow (eastward) beams respectively in terms of the contributions from the four different beam polarisation permutations, and these permutations are related to spin bits numbers in table one.


N(blue,up)=N(upUp)+N(downUp),N(blue,down)=N(downDown)+N(upDown)
Equation 2
N(yellow,up)=N(upUp)+N(upDown),N(yellow,down)=N(downDown+N(downUp)
Equation 3

(in e.g. N(upUp), The first arrow refers to yellow beam polarisation, the second to blue beam.)


Beam polarisation 4-bit spin bits
Yellow Blue
Up Up 5
Down Up 6
Up Down 9
Down Down 10
Table 1

The raw asymmetry is calculated for each RHIC fill, then divided by the polarisation for that fill to give the physics asymmetry. Final polarisation numbers (released December 2007) are used. The error on the raw asymmetry is calculated by propagation of the √(N) errors calculated for each particle yield. The final asymmetry error incorporates the polarisation error (statistical and systematic errors summed in quadrature). The fill-by-fill asymmetries for each K0S and Λ for each beam are shown in figures one and two. Anti-Λ results shall be forthcoming. An average asymmetry is calculated by performing a straight line χ2 fit through the fill-by-fill values with ROOT. Table one summarises the asymmetry results. The asymmetry error is the error from the ROOT fit and is statistical only. All fits give a good χ2 per degree of freedom and are consistent with zero within errors.

Fill-by-fill blue beam single spin asymmetry in K0s production
Figure 1a: K0S blue beam asymmetry
Fill-by-fill yellow beam single spin asymmetry in K0s production
Figure 1b: K0S yellow beam asymmetry
Fill-by-fill blue beam single spin asymmetry in Lambda production
Figure 2a: Λ blue beam asymmetry
Fill-by-fill yellow beam single spin asymmetry in Lambda production
Figure 2b: Λ yellow beam asymmetry

The above are summed over the entire pT range available. I also divide the data into different transverse momentum bins and calculate the asymmetry as a function of pT. Figures three and four show the pT-dependent asymmetries. No pT dependence is discernible.

Straight-line fit to pT-dependent K0s cross asymmetry for blue beam
Figure 3a: K0S pT-dependent blue beam AN
Straight-line fit to pT-dependent K0s cross asymmetry for yellow beam
Figure 3b: K0S pT-dependent yellow beam AN
Straight-line fit to pT-dependent Lambda cross asymmetry for blue beam
Figure 4a: Λ pT-dependent blue beam AN
Straight-line fit to pT-dependent Lambda cross asymmetry for yellow beam
Figure 4b: Λ pT-dependent yellow beam AN



Single spin asymmetry utilising relative luminosity

Single spin asymmetry making use of relative luminosity

I also calculate the asymmetry via an alternative method, making use of Tai Sakuma's relative luminosity work. The left-right asymmetry is defined as

Definition of left-right asymmetry
Equation 1

where NL is the particle yield to the left of the polarised beam. The decomposition of the up/down yields into contributions from the four different beam polarisation permutations is the same as given in the cross-asymmetry section (equations 2 and 3). Here, the yields must be scaled by the appropriate relative luminosity, giving the following relations:

Contributions to blue beam counts, scaled for luminosity
Equation 2
Contributions to yellow beam counts, scaled for luminosity
Equation 3

The relative luminosities R4, R5 and R6 are the ratios of luminosity for, respectively, up-up, up-down and down-up bunches to that for down-down bunches. I record the particle yields for each polarisation permutation (i.e. spin bits) on a run-by-run basis, scale each by the appropriate relative luminosity for that run, then combine yields from all the runs in a given fill to give fill-by-fill yields. These are then used to calculate a fill-by-fill raw asymmetry, which is scaled by the beam polarisation. The figures below show the resultant fill-by-fill asymmetry for each beam and particle species, summed over all pT. The fits are again satisfactory, and give asymmetries consistent with zero within errors, as expected.

K0s blue beam asymmetry using relative luminosity
Figure 1a: Blue beam asymmetry for K0S
K0s yellow beam asymmetry using relative luminosity
Figure 1b: Yellow beam asymmetry for K0S
Lambda blue beam asymmetry using relative luminosity
Figure 2a: Blue beam asymmetry for Λ
Lambda yellow beam asymmetry using relative luminosity
Figure 2b: Yellow beam asymmetry for Λ



V0 decays

V0 decays

The appearance of the decay of an unobserved neutral strange particle into two observed charged daughter particles gives rise to the terminology 'V0' to describe the decay topology. The following neutral strange species have been analysed:

Species Decay channel Branching ratio
K0S π+ + π- 0.692
Λ p + π- 0.639
anti-Λ anti-p + π+ 0.639

Candidate V0s are formed by combining together all possible pairs of opposite charge-sign tracks in an event. The invariant mass of the V0 candidate under different decay hypotheses can then be determined from the track momenta and the daughter masses (e.g. for Λ the positive daughter is assumed to be a proton, the negative daughter a π-minus). Raw invariant mass spectra are shown below. The spectra contain three contributions: real particles of the species of interest; neutral strange particles of a different species; combinatorial background from chance positive/negative track crossings.


Invariant mass spectrum for V0 candidates under K0s decay hypothesis
Figure 1: Invariant mass spectrum under K0s hypothesis
Invariant mass spectrum for V0 candidates under Lambda decay hypothesis
Figure 2: Invariant mass spectrum under Λ hypothesis
Invariant mass spectrum for V0 candidates under anti-Lambda decay hypothesis
Figure 3: Invariant mass spectrum under anti-Λ hypothesis

Selection cuts are applied to the candidates to suppress the background whilst maintaining as much signal as possible. There are two methods for reducing background; energy-loss particle identification and geometrical cuts on the V0 candidates.




Photon-jet with the Endcap (Ilya Selyuzhenkov)

Gamma-jets

W-analysis

2008

Year 2008 posts

 

01 Jan

January 2008 posts

 

2008.01.30 Selecting gamma-jet candidates out of the jet trees

Ilya Selyuzhenkov January 30, 2008

Data set

jet trees by Murad Sarsour for pp2006 run, runId=7136022 (~60K events, no triggerId cuts yet)

Jets gross features

  • Figure 1: Distribution of number of jets per event. Same data on a log scale is here.

  • Figure 2: Distribution of electromagnetic energy (EM) fraction, R_EM, for di-jet events (number of jets/event = 2).
    R_EM = [E_t(endcap)+E_t(barrel)]/E_t(total).
    Black histogram is for R_EM1 = max(Ra, Rb), red is for R_EM2 = min(Ra, Rb).
    Ra and Rb are EM fraction for jets in the di-jet event.
    Same data on a log scale is here.

     

Gamma-jet isolation cuts list:

  1. selecting di-jet events with one of the jet dominated by EM energy,
    and another one with more hadronic energy:

    R_EM1 >0.9 and R_EM2 < 0.9

  2. selecting di-jet events with jets pointing opposite in azimuth:

    cos(phi1 - phi2) < -0.9

  3. requiring the number of associated charged tracks with a first jet (with maximum EM fraction) to be less than 2:

    nChargeTracks1 < 2

  4. requiring the number of fired EEMC towers associated with a first jet (with maximum EM fraction) to be 1 or 2:

    0 < nEEMCtowers1 < 3

     

Applying gamma-jet isolation cuts

  • Figure 3: Distribution of eta vs number of EEMC towers for the first jet (with maximum EM fraction).
    Cuts:1-3 applied (no 0 < nEEMCtowers1 < 3 cut).

  • Figure 4: Distribution of transverse momentum, pt1, of the first jet (with maximum EM fraction)
    vs transverse momentum, pt2, of the second jet.
    Cuts:1-4 applied

  • Figure 5: Distribution of mean transverse momentum, < pt1 >, of the first jet (with maximum EM fraction)
    vs transverse momentum, pt2, of the second jet.
    Cuts:1-4 applied

  • Figure 6: Distribution of pseudorapidity, eta1, of the first jet (with maximum EM fraction)
    vs pseudorapidity, eta2, of the second jet.
    Cuts:1-4 applied

  • Figure 7: Distribution of azimuthal angle, phi1, of the first jet (with maximum EM fraction)
    vs azimuthal angle, phi2, of the second jet.
    Cuts:1-4 applied

  • Figure 8: Distribution of transverse momentum, pt1, of the first jet (with maximum EM fraction)
    vs transverse energy sum for the EEMC towers associated with this jet.
    Cuts:1-4 applied

  • Figure 9: Distribution of transverse momentum, pt1, of the first jet (with maximum EM fraction)
    vs transverse momentum, pt2, of the second jet.
    Cuts:1-4 + Et(EEMC) > 3.0 GeV

 

02 Feb

February 2008 posts

 

2008.02.13 Gamma-jet candidates: EEMC response

Ilya Selyuzhenkov February 13, 2008

Data sample

Gamma-jet selection cuts are discussed here. There are 278 candidates found for runId=7136022.
Transverse momentum distribution for the gamma-jet candidates can be found here.

Vertex z distribution for di-jet and gamma-jet events

  • Figure 1: Vertex z distribution.

    Red line presents gamma-jet candidates (scaled by x50). Black is for all di-jet events.
    Same data on a log scale is here.

  • Figure 2: Average vertex z as a function of transverse momentum of the fist jet (with a largest EM energy fraction).
    Red is for gamma-jet candidates. Black is for all di-jet events.
    Strong deviation from zero for gamma-jet candidates at pt < 5GeV?

     

EEMC response for the gamma-jet candidate

EEMC response event by event for all 278 gamma-jet candidate can be found in this pdf file.
Each page shows SMD/Tower energy distribution for a given event:

  1. First row on each page shows SMD response
    for the sector which has a maximum energy deposited in the EEMC Tower
    (u-plane is on the left, v-plane is on the right).

  2. In the left plot (u-plane energy distribution) numerical values for
    pt of the first jet (with maximum EM fraction) and the second jet are given.

  3. In addition, fit results assuming gamma (single Gaussian, red line) or
    neutral pion (double Gaussian, blue line ~ red+green) hypotheses are given.

  4. m_{gamma gamma} value (it is shown in the right plot for v-plane).

    If m_{gamma gamma} value is negative, then the reconstruction procedure has failed
    (for example, no uv-strips intersection found, or tower energy and uv-strips intersection point mismatch, etc).
    EEMC response for these "bad" events can be found in this pdf file.

    If reconstruction procedure succeded, then
    m_{gamma gamma} gives reconstructed invariant mass assuming that two gammas hit the calorimeter.

    Figure 3: invariant mass distribution (assuming pi0 hypothesis).

    Note, that I'm still working on my fitting algorithm (which is not explained here),
    and fit results and the invariant mass distribution will be updated.

     

  5. It is also shown the ratio for each u/v plane
    of the integrated single Gaussian fit (red line) to the total energy in the plane
    (look for "gamma U/V " values on the right v-plane plot).

  6. Second and third rows on each page show the energy deposition in the
    tower, pre-shower1, pre-shower2, and post-shower as a function of eta:phi (etaBin:phiBin).

  7. Last row shows the hit distribution in the SMD for all sectors
    (u-plane on the left, v-plane of the right).

Playing with a different cuts

Trying to isolate the real gammas which hits the calorimeter,
I have sorted events into different subsets based on the following set of cuts:

  1. EEMC gamma-jet cuts (energetic photon hits EEMC with pt similar or greater to that of the opposite jet)

    if (invMass < 0) reject
    if (jet2_pt > jet1_pt) reject
    if (jet1_pt < 7) reject
    if (minFraction < 0.75) reject
    (minFraction = gamma U/V - is a fraction of the integrated single Gaussian peak to the total energy in the uv-plane)

    Figure 4: Sample gamma-jet candidate EEMC response
    (all gamma-jet candidates selected according to these conditions can be found in this pdf file):

  2. EEMC pi0 cuts:

    if (invMass < 0) reject
    if (jet2_pt < jet1_pt) reject
    if (jet2_pt < 7) reject
    if (minFraction < 0.75) reject

    Event by event EEMC response for pi0 (di-jet) candidates
    selected according to these conditions can be found in this pdf file.

 

2008.02.20 Gamma-jet candidates: more statistics from jet-trees

Ilya Selyuzhenkov February 20, 2008

Short summary

After processing all available jet-trees for pp2006 (ppProductionLong),
and applying all "gamma-jet" cuts (which are described below):

  • there are 47K di-jet events selected

  • for pt1>7GeV there are 5,4K gamma-jet candidates (3,7K with an additional cut of pt1>pt2)

  • Figure 1: 2,4K events with both pt1, pt2 > 7GeV

  • 721 candidates within a range of pt1>pt2 and both pt1, pt2 > 7 GeV

Data set

jet trees by Murad Sarsour for pp2006 run, number of runs processed: 323
4.7M di-jet events found (no triggerId cuts yet)

Di-jets gross features

  • Figure 2: Distribution of electromagnetic energy (EM) fraction, R_EM, for di-jet events (number of jets/event = 2).
    R_EM = [E_t(endcap)+E_t(barrel)]/E_t(total).
    Black histogram is for R_EM1 = max(Ra, Rb), red is for R_EM2 = min(Ra, Rb).
    Ra and Rb are EM fraction for jets in the di-jet event.
    Same data on a log scale is here.

     

Gamma-jet isolation cuts:

  1. selecting di-jet events with one of the jet dominated by EM energy,
    and another one with more hadronic energy:

    R_EM1 >0.9 and R_EM2 < 0.9

  2. selecting di-jet events with jets pointing opposite in azimuth:

    cos(phi1 - phi2) < -0.9

  3. requiring the number of associated charged tracks with a first jet (with maximum EM fraction) to be less than 2:

    nChargeTracks1 < 2

  4. requiring the number of fired EEMC towers associated with a first jet (with maximum EM fraction) to be 1 or 2:

    0 < nEEMCtowers1 < 3

     

Applying gamma-jet isolation cuts

  • Figure 3: Distribution of eta vs number of EEMC towers for the first jet (with maximum EM fraction).
    Cuts:1-3 applied (no 0 < nEEMCtowers1 < 3 cut).

  • Figure 4: Distribution of transverse momentum, pt1, of the first jet (with maximum EM fraction)
    vs transverse momentum, pt2, of the second jet.
    Cuts:1-4 applied

  • Figure 5: Distribution of mean transverse momentum, < pt1 >, of the first jet (with maximum EM fraction)
    vs transverse momentum, pt2, of the second jet.
    Cuts:1-4 applied

  • Figure 6: Distribution of pseudorapidity, eta1, of the first jet (with maximum EM fraction)
    vs pseudorapidity, eta2, of the second jet.
    Cuts:1-4 applied

  • Figure 7: Distribution of azimuthal angle, phi1, of the first jet (with maximum EM fraction)
    vs azimuthal angle, phi2, of the second jet.
    Cuts:1-4 applied

  • Figure 8: Distribution of transverse momentum, pt1, of the first jet (with maximum EM fraction)
    vs transverse energy sum for the EEMC towers associated with this jet.
    Cuts:1-4 applied

  • Figure 9: Distribution of transverse momentum, pt1, of the first jet (with maximum EM fraction)
    vs transverse momentum, pt2, of the second jet.
    Cuts:1-4 + Et(EEMC) > 3.0 GeV

 

2008.02.27 Tower based clustering algorithm, and EEMC/BEMC candidates

Ilya Selyuzhenkov February 27, 2008

Gamma-jet candidates before applying clustering algorithm

Gamma-jet isolation cuts:

  1. selecting di-jet events with the first jet dominated by EM energy,
    and the second one with a large fraction of hadronic energy:

    R_EM1 >0.9 and R_EM2 < 0.9

  2. selecting di-jet events with jets pointing opposite in azimuth:

    cos(phi1 - phi2) < -0.8

  3. requiring no charge tracks associated with a first jet (jet with a maximum EM fraction):

    nCharge1 = 0

Figure 1: Transverse momentum

Figure 2: Pseudorapidity

Figure 3: Azimuthal angle

Tower based clustering algorithm

  • for each gamma-jet candidate finding a tower with a maximum energy
    associated with a jet1 (jet with a maximum EM fraction).

  • Calculating energy of the cluster by finding all adjacent towers and adding their energy together.

  • Implementing a cut based on cluster energy fraction, R_cluster, where

    R_cluster is defined as a ratio of the cluster energy
    to the total energy in the calorimeter associated with a jet1.
    Note, that with a cut Ncharge1 =0, energy in the calorimeter is equal to the jet energy.

 

Distribution of cluster energy vs number of towers fired in EEMC/BEMC

Figure 4: R_cluster vs number of towers fired in EEMC (left) and BEMC (right). No pt cuts.

Figure 5: R_cluster vs number of towers fired in EEMC (left) and BEMC (right). Additional cut: pt1>7GeV

Figure 6: jet1 pseudorapidity vs number of towers fired in EEMC (left) and BEMC (right).

 

R_cluster>0.9 cut: EEMC vs BEMC gamma-jet candidates

EEMC candidates: nTowerFiredBEMC=0
BEMC candidates: nTowerFiredEEMC=0

Figure 7: Pseudorapidity (left EEMC, right BEMC candidates)

Figure 8: Azimuthal angle (left EEMC, right BEMC candidates)

Figure 9: Transverse momentum (left EEMC, right BEMC candidates)

 

Number of gamma-jet candidates with an addition pt cuts

Figure 10: Transverse momentum (left EEMC, right BEMC candidates): pt1>7GeV

Figure 11: Transverse momentum (left EEMC, right BEMC candidates): pt1>7 and pt2>7

03 Mar

March 2008 posts

 

2008.03.03 EEMC SMD: u/v-strip energy distribution

Ilya Selyuzhenkov March 03, 2008

Data set: ppLongitudinal, runId = 7136033.

Some observations/questions:

  1. In general distributions look clean and good

  2. Sectors 7 and 9 for v-plane and sector 7 for u-plane are noise.

  3. Sector 9 has a hot strip (id ~ 120)

  4. In sector 3, strips id=0-5 in v-plane are hot (see figure 2 right, bottom)

  5. Sectors 2 and 8 in u-plane and sectors 3 and 9 in v-plane have missing strips id=283-288?

  6. Strips 288 are always empty?

Figure 1:Average energy E in the strip vs sector and strip number (max < E > = 0.0027)
same figure on a log scale

Figure 2: Average energy E for E>0.02 (max < E > = 0.0682)
Same figure on a log scale

2008.03.12 Gamma-jet candidates: 2-gammas invariant mass and Eemc response

Ilya Selyuzhenkov March 12, 2008

Gamma-jet candidates: 2-gammas invariant

Note: Di-jet transverse momentum distribution for these candidates can be found on figure 11 at this page

Figure 1:Invariant mass distribution for gamma-jet candidates assuming pi0 (2-gammas) hypothesys

Figure 2:Invariant mass distribution for gamma-jet candidates assuming pi0 (2-gammas) hypothesys
with an additional SMD isolation cut: gammaFraction >0.75
GammaFraction is defined as ratio of the integral
other SMD strips for the first peak to the total energy in the sector

 

EEMC response for the gamma-jet candidates (gammaFraction >0.75)

  1. pdf file (first 100 events) with event by event EEMC response for the candidates reconstructed into pion mass (gammaFraction >0.75)

  2. pdf file with event by event EEMC response for the candidates not reconstructed into pion mass
    (second peak not found), but has a first peak with gammaFraction >0.75.

 

2008.03.20 Sided residual and chi2 distribution for gamma-jet candidates

Ilya Selyuzhenkov March 20, 2008

Side residual (no pt cut on gamma jet-candidates)

The procedure to discriminate gamma candidate from pions (and other background)
based on the SMD response is described at Pibero's web page.

 

Figure 1: Fit integral vs maximum residual for gamma-jet candidates requesting
no energy deposited in the EEMC pre-shower 1 and 2
(within a 3x3 clusters around tower with a maximum energy).

Black line is defined from MC simulations (see Jason's simulation web page, or Pibero's page above).

 

Figure 2: Fit integral vs maximum residual for gamma-jet candidates requesting requesting
no energy deposited in pre-shower 1 cluster and
no energy deposited in post-shower cluster (this cut is not really essential in demonstrating the main idea)

 

Figure 3: Fit integral vs maximum residual for gamma-jet candidates requesting requesting
non-zero energy deposited in both clusters of pre-shower 1 and 2

 

Side residual: first and second jet pt are greater than 7GeV

Event by event EEMC response for gamma-jet candidates for the case of
no energy deposited in the EEMC pre-shower 1 and 2 can be found in this pdf file

 

Figure 4: Fit integral vs maximum residual for gamma-jet candidates requesting
no energy deposited in the EEMC pre-shower 1 and 2

 

Figure 5: Fit integral vs maximum residual for gamma-jet candidates requesting requesting
no energy deposited in pre-shower 1 cluster and
no energy deposited in post-shower cluster

 

Figure 6: Fit integral vs maximum residual for gamma-jet candidates requesting requesting
non-zero energy deposited in both clusters of pre-shower 1 and 2

 

Chi2 distribution for gamma-jet candidates

Monte Carlo shape

Event Monte Carlo shape allows to distinguish gammas from background by cutting at chi2/ndf < 0.5
(although the distribution looks wider than for the case of Will's shape).

 

Figure 7: Chi2/ndf for gamma-jet candidates using Monte Carlo shape requesting
no energy deposited in both clusters of pre-shower 1 and 2

 

Figure 8: Chi2/ndf for gamma-jet candidates using Monte Carlo shape requesting
non-zero energy deposited in both clusters of pre-shower 1 and 2

 

Will''s shape

Less clear where to cut on chi2?

 

Figure 9: Chi2/ndf for gamma-jet candidates using Monte Carlo shape requesting
no energy deposited in both clusters of pre-shower 1 and 2

 

Figure 10: Chi2/ndf for gamma-jet candidates using Monte Carlo shape requesting
non-zero energy deposited in both clusters of pre-shower 1 and 2 

 

2008.03.26 Sided residual and chi2 distribution for gamma-jet candidates (pre1,2 sorted)

Ilya Selyuzhenkov March 26, 2008

gamma-jet candidates (no pt cut)

Definitions:

  • F_peak - integral for a fit within [-2,2] strips around SMD u/v peak
  • D_peak - integral over the data within [-2,2] strips around SMD u/v peak
  • D_tail^max (D_tail^min) - maximum (minimum) integral over the data tail within +-[3,30] strips from a SMD u/v peak
  • F_tail is the integral over the fit tail within [3,30] strips from a SMD u/v peak.
  • Maximum residual = D_tail^max - F_tail

All results are for combined distributions from u and v planes: ([u]+[v])/2
Gamma-jet isolation cuts described here
Additional quality cuts:

  1. Matching between 3x3 tower cluster and u-v high strip intersection
  2. At least 4 strips fired within [-2,2] strips from a peak

Figure 1: F_peak vs maximum residual
for various cuts on energy deposited in the EEMC pre-shower 1 and 2
(within a 3x3 clusters around tower with a maximum energy).

 

Figure 2: F_data vs D_tail^max
Note:This plot is fit independend (only the peak position is defined based on the fit)

 

Figure 3: F_data vs D_tail^max-D_tail^max

 

Figure 4: Gamma transverse momentum vs jet transverse momentum

 

gamma-jet candidates: pt > 7GeV

Figure 5: F_peak vs maximum residual
for various cuts on energy deposited in the EEMC pre-shower 1 and 2
(within a 3x3 clusters around tower with a maximum energy).

Figure 6: F_data vs D_tail^max
Note:This plot is fit independend (only the peak position is defined based on the fit)

Figure 7: F_data vs D_tail^max-D_tail^max

Figure 8: Gamma transverse momentum vs jet transverse momentum

 

gamma-jet candidates: eta, phi, and max[u,v] strip distributions (no pt cuts)

Figure 9: Gamma pseudorapidity vs jet pseudorapidity

 

Figure 10: Gamma azimuthal angle vs jet azimuthal angle
Note: for the case of Pre1>1 && Pre2==0 there is an enhancement around phi_gamma = 0?

 

Figure 11: maximum strip in v-plane vs maximum strip in u-plane

 

Chi2 distribution for gamma-jet candidates (no pt cuts)

Figure 12:Chi2/ndf for gamma-jet candidates using Monte Carlo shape (combined for [u+v]/2 plane )

Figure 13:Chi2/ndf for gamma-jet candidates (combined for [u+v]/2 plane ) using Will's shape

 

2008.03.28 EEMC SMD shapes: gamma's from gamma-jets (data), MC, and eta-meson analysis

Ilya Selyuzhenkov March 28, 2008

Some observations:

  1. SMD data-driven shapes from different analysis are in a good agreement (Figure 1, upper left plot)
  2. Overall MC shape is too narrow compared to the data shapes (Figure 1, upper left plot)
  3. Shapes are similar with or without gamma-jet 7GeV pt cut (compare Figures 1 and 2),
    what may indicate that shape is independent on energy (at least within our kinematic limits).
  4. Data-driven and MC shapes are getting close to each other (Figure 4, upper left plot)
    when requiring no energy above threshold in both preshower layers and
    with suppressed contribution from pi0 background.
    The latter is achieved by using the information on
    reconstructed invariant mass of 2gamma candidates (compare Figure 3 and 4).

    One interpretation of this can be that in Monte Carlo simulations
    the contribution from the material in front of the detector is underestimated

  5. Energy distribution for each strip in the SMD peak does not looks like a Gaussian (Figure 5),
    what makes very difficult to interpret results obtained from chi2 analysis (Figure 6-8).
  6. Triple Gaussian fit gives a better description of the data shapes,
    compared to the double Gaussian function (compare red and black lines on Figure 1-4)

 

Figure 1: EEMC SMD shape comparison for various preshower cuts
(black points shows u-plane shape only, v-plane results can be found here)

 

Figure 2: EEMC SMD shape comparison for various preshower cuts with gamma-jet pt cut of 7GeV
(black points shows u-plane shape only, v-plane results can be found here)

 

Figure 3: Shapes with an additional cut on 2-gamma candidates within pi0 invariant mass range.
Sample invariant mass distribution using "simple" pi0 finder can be found here
(black points shows u-plane shape only, v-plane results can be found here)

 

Figure 4: Shapes for the candidates when "simple" pi0 finder failed to find a second peak
(black points shows u-plane shape only, v-plane results can be found here)

 

Figure 5: Strip by strip SMD energy distribution.
Only 12 strips from the right side of the maximum are shown.
Zero strip (first upper left plot) corresponds to the high strip in the shape
Note, that already at the 3rd strip from a peak,
RMS values are comparable to those for a mean, and for a higher strips numbers RMS starts to be bigger that mean.
(results for u-plane only, v-plane results can be found here)

 

Comparing chi2 distributions for gamma-jet candidates using MC, Will, and Pibero's shapes

Results for side residual (together with pt, eta, phi distributions) for gamma-jet candidates can be found at this web page

Red histograms on Figures 6-8 shows chi2 distribution from MC-photons (normalized at chi2=1.4)
Blue histograms on Figures 6-8 shows chi2 distribution from MC-pions (normalized at chi2=1.4)

Figure 6: Chi2/ndf for gamma-jet candidates using Monte Carlo shape

 

Figure 7: Chi2/ndf for gamma-jet candidates using Will's shape (derived from eta candidates based on Weihong's pi0-finder)

Figure 8: Chi2/ndf for gamma-jet candidates using Pibero's shape (derived from eta candidates)

 

04 Apr

April 2008 posts

 

2008.04.02 EEMC SMD shapes: data-driven (eta, gamma-jet) vs Monte Carlo (single gamma, gamma-jet)

Ilya Selyuzhenkov April 02, 2008

Some observations:

  1. SMD data-driven shapes from eta-meson and gamma-jet studies
    are in a good agreement for different preshower conditions
    (compage Fig.1 green circles/triangles in upper-left/bottom-right plots)
  2. single gamma MC shapes show preshower dependance,
    but they are still narrower compared to the data shapes
    (compare Fig.1 green circles vs blue open squares)
  3. MC shapes for gamma-jet and single gamma are consistent (Fig.1, bottom right plot)

 

Figure 1: EEMC SMD shape comparison for various preshower cuts
Note:Only MC gamma-jet shape (open red squares) is the same on all plots

2008.04.02 Sided residual: Using data driven gamma-jet shape (3 gaussian fit)

Ilya Selyuzhenkov April 02, 2008

Figure 1: Side residual for various cuts on energy deposited in the EEMC pre-shower 1 and 2
No EEMC SMD based cuts

 

Figure 2: Side residual for various cuts on energy deposited in the EEMC pre-shower 1 and 2
"Simple" pi0 finder can not find a second peak

 

Figure 3: Side residual for various cuts on energy deposited in the EEMC pre-shower 1 and 2
"Simple" pi0 finder reconstruct the invarian mass within [0.1,0.18] range

 

Figure 4: Side residual distribution (Projection for side residual in Figs.1-3 on vertical axis)

 

Figure 5: Signal (green: m < 0) vs background (black, red) separation

2008.04.02 Sided residual: single gamma Monte-Carlo simulations

Ilya Selyuzhenkov April 02, 2008

Side residual: single gamma Monte-Carlo simulations

Figure 1: Side residual for various cuts on energy deposited in the EEMC pre-shower 1 and 2
No EEMC SMD based cuts

2008.04.03 chi2-shape subtraction for different Preshower conditions

Ilya Selyuzhenkov April 03, 2008

Request from Hal Spinka:

Hi Ilya,

I think you gave up on the chi-squared method too quickly, and am sorry I missed the phone meeting last week. So, I would like to make a request that will hopefully take a minimal amount of your time to show that all is okay. Then, if there is a delay in getting the sided residual information out and into the beam use request, you can still fall back on the chi-squared method.

In your March 28 posting, Figure 8 at the bottom, I would like to get numerical values for the events per bin for the black curves. I won't use the preshower1>0 and preshower2=0 data, so those you don't need to send. Also, I won't use the red or blue curve information.

I think your problem has been that you normalized your curves at chi-squared/ndf = 1.4 instead of the peak. What I plan to do is to normalize the (pre1=0, pre2=0) to the (pre1=0, pre2>0) data in the peak and subtract. The (pre1=0, pre2=0) set should have some single photons, but also some multiple photons. The (pre1=0, pre2>0) should also have single photons, and more multiple photons, since the chance that one of them will convert is larger. The difference should look roughly like your blue curve, though perhaps not exactly if Pibero's mean shower shape is not perfect (which it isn't). I will do the same thing with taking the difference between (pre1>0, pre2>0) and (pre1=0, pre2=0), and again the difference should look roughly like your blue curve. The (pre1>0, pre2>0) data should have even larger fraction of multiple photons than either of the other two data sets. I would expect the two difference curves to look approximately the same.

Hope this is possible for you to do. Since our reduced chi-squared curve looks so much like the one from CDF, I am pretty confident that we are okay, but this should be checked to convince people that we are not doing anything terribly wrong.

Reply by Ilya:

Dear Hal,

I have tried to implement your idea and produce a figure attached.

There are 4 plots in it:

1. Upper left plot shows normalized to unity (at maximum) chi2 distribution (obtained with Pibero shape for gamma-jet candidates) for a different pre1, pre2 conditions

2. Upper right plot shows bin-by-bin difference: a) between normalized chi2 for pre1=0, pre2>0 and pre1=0, pre2=0 (red) and b) between normalized chi2 for pre1>0, pre2>0 and pre1=0, pre2=0 (blue)

3. Bottom left Same as upper right, but normalization were done based on the integral within [-4,4] bins around maximum.

4. Bottom right Same as for upper right, but with a different normalization ([-4,4] bins around maximum)

I have also tried to normalized by the total integral, but the results looks similar.

 

Figure 1: See description above

 

Figure 2: Same without log scale (See description above)

2008.04.09 Applying gamma-jet reconstruction algorithm for gamma-jet simulated events

Ilya Selyuzhenkov April 09, 2008

Data sample:
Monte-Carlo gamma-jet sample for partonic pt range of 5-7, 7-9, 9-11,11-15, 15-25, 25-35 GeV.

Analysis: Simulated MuDst files were first processed through jet finder algorithm (thanks to Renee Fatemi),
and later analyzed by applying gamma-jet isolation cuts (see this link for details) and studying EEMC SMD response (see below).
To test the algorithm, Geant records were not used in this analysis.
Further studies based on Geant records (yield estimates, etc) are ongoing.

EESMD shapes comparison

Figure 1:Comparison between shower shape profile for data and MC.
Black circles shows results for MC gamma-jet sample (all partonic pt).
For v-plane results see this figure

 

Correlation between gamma and jet pt, eta, phi

Figure 2:Gamma vs jet transverse momentum.

 

Figure 3:Gamma vs jet azimuthal angle.

 

Figure 4:Gamma vs jet pseudo-rapidity.

 

Results from maximum sided residua study

Definitions for F_peak, D_peak, D_tail^max (D_tail^min) can be found here

Figure 5:F_peak vs maximum residual
for various cuts on energy deposited in the EEMC pre-shower 1 and 2
(within a 3x3 clusters around tower with a maximum energy).
Shower shape used to fit data is fixed to the shape from the previous gamma-jet study of real events
(see black point on Fig.1 [upper left plot] at this page)

 

Figure 6: F_peak vs D_tail^max: click here
Figure 7: F_peak vs D_tail^max-D_tail^min: click here

Postshower to SMD[uv] energy ratio

Figure 8:Logarithmic fraction of energy in post shower (3x3 cluster) to the total energy in SMD u- and v-planes

 

Figure 8a:
Same as figure 8, but for gamma-jet candidates from the real data (no pt cuts).
Logarithmic fraction of energy in post shower (3x3 cluster) to the total energy in SMD u- and v-planes

 

Figure 8b:
Comparison between gamma-jet candidates from data with different preshower conditions.
Points are normalized in peak to the case of pre1 > 0, pre2 > 0

Logarithmic fraction of energy in post shower (3x3 cluster) to the total energy in SMD u- and v-planes

 

Figure 8c:
Comparison between gamma-jet candidates from Monte-Carlo simulations with different preshower conditions.
Points are normalized in peak to the case of pre1 > 0, pre2 > 0

Logarithmic fraction of energy in post shower (3x3 cluster) to the total energy in SMD u- and v-planes

 

Additional QA plots

Figure 9: Jet neutral energy fraction
Figure 10: High v-strip vs u-strip
Figure 11: energy post shower (3x3 cluster)
Figure 12: Peak energy SMD-u
Figure 13: Peak energy SMD-v
Figure 14: Gamma phi
Figure 15: Gamma pt
Figure 16: Gamma eta
Figure 17: Delta gamma-jet pt
Figure 18: Delta gamma-jet eta
Figure 19: Delta gamma-jet phi

 

chi2 distributions

Figure 20:chi2 distribution using "standard" MC shape

 

Figure 21:chi2 distribution using Pibero shape

2008.04.16 Sided residual: Data Driven MC vs raw MC vs 2006 data

Ilya Selyuzhenkov April 16, 2008

Figure 1: Sided residual for raw MC (partonic pt 9-11)

 

Figure 2: Sided residual for data-driven MC (partonic pt 9-11)

 

Figure 3: Sided residual for data (pp Longitudinal 2006)

 

Different analysis cuts vs number of events which passed the cut

  1. N_events : total number of di-jet events found by the jet-finder for gamma in eta region [1,2]
    (Geant record is used to get this number)
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_{3x3cluster} > 0.9 : Energy in 3x3 cluster of EEMC tower to the total jet energy.
  4. R_EM^jet < 0.9 : neutral energy fraction cut for on away side jet
  5. N_ch=0 : no charge tracks associated with a gamma candidate
  6. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  7. N_(5-strip clusler)^u > 3 : minimum number of strips in EEMC SMD u-plane cluster around peak
  8. N_(5-strip cluster)^v > 3 : minimum number of strips in EEMC SMD v-plane cluster around peak
  9. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  10. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluser

Figure 4: Number of events which passed various cuts (MC data, partonic pt 9-11)

 

2008.04.17 Sided residual: Data Driven MC vs raw MC (partonic pt=5-35) vs 2006 data

Ilya Selyuzhenkov April 17, 2008

MC data for different pt weigted according to Michael Betancourt web page:
weight = xSection[ptBin] / xSection[max] / nFiles

Figure 1: Sided residual for raw MC (partonic pt 5-35)
(same plot for partonic pt 9-11)

 

Figure 2: Sided residual for data-driven MC (partonic pt 5-35)
(same plot for partonic pt 9-11)

 

Figure 3: Sided residual for data (pp Longitudinal 2006)

 

Figure 4: Sided residual for data (pp Longitudinal 2006)

 

Figure 5: Sided residual for data (pp Longitudinal 2006)

 

Figure 6: pt(gamma) from geant record vs
pt(gamma) from energy in 3x3 tower cluster and position for uv-intersection wrt vertex
(same on a linear scale)

 

Figure 7: pt(gamma) from geant record vs
pt(jet) as found by the jet-finder

 

Figure 8: gamma pt distribution:
data-driven MC (red) vs gamma-jet candidates from pp2006 longitudinal run (black).
MC distribution normalized to data at maximum for each preshower condition

 

Different analysis cuts vs number of events which passed the cut

  1. N_events : total number of di-jet events found by the jet-finder for gamma in eta region [1,2]
    (Geant record is used to get this number)
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_{3x3cluster} > 0.9 : Energy in 3x3 cluster of EEMC tower to the total jet energy.
  4. R_EM^jet < 0.9 : neutral energy fraction cut for on away side jet
  5. N_ch=0 : no charge tracks associated with a gamma candidate
  6. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  7. N_(5-strip clusler)^u > 3 : minimum number of strips in EEMC SMD u-plane cluster around peak
  8. N_(5-strip cluster)^v > 3 : minimum number of strips in EEMC SMD v-plane cluster around peak
  9. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  10. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluser

Figure 9: Number of events which passed various cuts (MC data, partonic pt 5-35)
Red: cuts applied independent
Black: cuts applied sequential from left to right

 

2008.04.23 Gamma-jet candidates: pp2006 data vs data-driven MC (gamma-jet and bg:jet-jet)

Ilya Selyuzhenkov April 23, 2008

Sided residual: pp2006 data vs data-driven MC (gamma-jet and bg:jet-jet)

MC data for different partonic pt are weigted according to Michael Betancourt web page:
weight = xSection[ptBin] / xSection[max] / nFiles

Figure 1:Sided residual for data-driven gamma-jet MC events (partonic pt 5-35)

 

Figure 2:Sided residual for data-driven jet-jet MC events (partonic pt 3-55)

 

Figure 3:Sided residual for data (pp Longitudinal 2006)

 

Figure 4:pt(gamma) vs pt(jet) for data-driven gamma-jet MC events (partonic pt 5-35)

 

Figure 5:pt(gamma) vs pt(jet) for data-driven jet-jet MC events (partonic pt 3-55)

 

Figure 6:pt(gamma) vs pt(jet) for data (pp Longitudinal 2006)

05 May

May 2008 posts

 

2008.05.05 pt-distributions, sided residual (data vs dd-MC g-jet and bg di-jet)

Ilya Selyuzhenkov May 05, 2008

Data samples:

  • pp2006(long) - 2006 pp production longitudinal data after applying gamma-jet aisolation cuts
    (jet-tree sample: 4.114pb^-1 from Jamie script, 3.164 pb^1 analyses).
  • gamma-jet - Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV
  • bg jets - Pythia di-jet sample (~4M events). Partonic pt range 3-65 GeV

Figure 1:pt distribution. MC data are scaled to the same luminosity as data
(Normalization factor: Luminosity * sigma / N_events).

 

 

Figure 2:Integrated gamma yield vs pt.
For each pt bin yield is defined as the integral from this pt up to the maximum available pt.
MC data are scaled to the same luminosity as data.

 

Figure 3:Signal to background ratio (all results divided by the data)

 

Sided residual: pp2006 data vs data-driven MC (gamma-jet and bg:jet-jet)

You can find sided residual 2-D plots here

Figure 4:Maximum sided residual for pt_gamma>7GeV; pt_jet>7GeV

 

Figure 5:Fitted peak for pt_gamma>7GeV; pt_jet>7GeV

 

Figure 6:Max data tail for pt_gamma>7GeV; pt_jet>7GeV

 

Figure 7:Max minus min data tails for pt_gamma>7GeV; pt_jet>7GeV

 

Figure 8:Shower shapes pt_gamma>7GeV; pt_jet>7GeV

2008.05.08 y:x EEMC position for gamma-jet candidates

Ilya Selyuzhenkov May 08, 2008

y:x EEMC position for gamma-jet candidates

Figure 1:y:x EEMC position for gamma-jet candidates:
Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.

 

Figure 2:y:x EEMC position for gamma-jet candidates:
Pythia QCD bg sample (~4M events). Partonic pt range 3-65 GeV.

 

Figure 3:y:x EEMC position for gamma-jet candidates:
pp2006 (long) data [eemc-http-mb-l2gamma:137641 trigger]

 

Figure 3b:y:x EEMC position for gamma-jet candidates:
pp2006 (long) data [eemc-http-mb-l2gamma:137641 trigger]
pt cut of 7 GeV for gamma and 5GeV for the away side jet has been applied.

high u vs. v strip for gamma-jet candidates

 

Figure 4:High v-strip vs high u-strip.
Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.

Figure 5:High v-strip vs high u-strip:
Pythia QCD bg sample (~4M events). Partonic pt range 3-65 GeV.

 

Figure 6:High v-strip vs high u-strip:
pp2006 (long) data [eemc-http-mb-l2gamma:137641 trigger]

 

Figure 6b:High v-strip vs high u-strip:
pp2006 (long) data [eemc-http-mb-l2gamma:137641 trigger]
pt cut of 7 GeV for gamma and 5GeV for the away side jet has been applied.

 

2008.05.09 Gamma-jet candidates pt-distributions and TPC tracking

Ilya Selyuzhenkov May 09, 2008

Detector eta cut study (1< eta < 1.4):

Figure 1:Gamma pt distribution. MC data are scaled to the same luminosity as data
(Normalization factor: Luminosity * sigma / N_events).

 

Figure 2:Gamma yield vs pt. MC data are scaled to the same luminosity as data.

 

Figure 3:Signal to background ratio (MC results are normalized to the data)

2008.05.14 Gamma-cluster to jet energy ratio and away side jet pt matching

Ilya Selyuzhenkov May 14, 2008

Gamma-cluster to jet1 energy ratio

  • Correlation between gamma-candidate 3x3 cluster energy ratio (R_cluster) and
    number of EEMC towers in a jet1 can be found here (Fig. 4).

  • Gamma pt distribution, yield and signal to background ratio plots
    for a cut of R_cluster >0.9 can be found here (Figs. 1-3).

  • Gamma pt distribution, yield and signal to background ratio plots
    for a cut of R_cluster >0.99 are shown below in Figs. 1-3.
    One can see that by going from R_cluster>0.9 to R_cluster>0.99
    improves signal to background ratio from ~ 1:10 to ~ 1:5 for gamma pt>10 GeV

Figure 1:Gamma pt distribution for R_cluster >0.99.
MC results scaled to the same luminosity as data
(Normalization factor: Luminosity * sigma / N_events).

 

Figure 2:Integrated gamma yield vs pt for R_cluster >0.99
For each pt bin yield is defined as the integral from this pt up to the maximum available pt.
MC results scaled to the same luminosity as data.

 

Figure 3:Signal to background ratio for R_cluster >0.99 (all results divided by the data)
Compare this figure with that for R_cluster>0.9 (Fig. 3 at this link)

 

Gamma and the away side jet pt matching

Figure 4: pt asymmetry between gamma and the away side jet (R_cluster >0.9)
for a three data samples (pp2006[long] data, gamma-jet MC, QCD jets background).
pt cut of 7 GeV for both gamma and jet has been applied.

Figure 5: signal to background ratio (R_cluster >0.9)
as a function of pt asymmetry between gamma and the away side jet
pt cut of 7 GeV for both gamma and jet has been applied.

 

 

Figure 6: pt asymmetry between gamma and the away side jet (R_cluster >0.99)
for a three data samples (pp2006[long] data, gamma-jet MC, QCD jets background).
pt cut of 7 GeV for both gamma and jet has been applied.

Figure 7: signal to background ratio
as a functio of pt asymmetry between gamma and the away side jet (R_cluster >0.99)
pt cut of 7 GeV for both gamma and jet has been applied.

 

 

Figure 8: pt asymmetry between gamma and the away side jet (R_cluster >0.99)
for a three data samples (pp2006[long] data, gamma-jet MC, QCD jets background).
pt cut of 7 GeV for gamma and 5GeV for the away side jet has been applied.

Figure 9: signal to background ratio
as a function of pt asymmetry between gamma and the away side jet (R_cluster >0.99)
pt cut of 7 GeV for gamma and 5GeV for the away side jet has been applied.

 

2008.05.15 Vertex z distribution for pp2006 data, MC gamma-jet and QCD jets events

Ilya Selyuzhenkov May 15, 2008

Figure 1:Vertex z distribution for pp2006 (long) data [eemc-http-mb-l2gamma:137641 trigger]
Note: In the upper right plot (pre1=0, pre2>0) one can see
a hole in the acceptance in the range bweeeen z_vertex -10 to 30 cm (probably due to SVT construction)

 

Figure 1b:Vertex z distribution for pp2006 (same as Fig. 1, but on a linear scale)

 

Figure 2:Vertex z distribution for three different data samples
MC results scaled to the same luminosity as data

 

Figure 3:Vertex z distribution for three different data samples
pt cut of 7 GeV for gamma and 5GeV for the away side jet has been applied.

2008.05.20 Shower shapes sorted by pre-shower, z-vertex and gamma's eta, phi, pt

Ilya Selyuzhenkov May 20, 2008

Gamma-jet algorithm and isolation cuts:

  1. Selecting only di-jet events identified by the STAR jet finder algorithm,
    with jets pointing opposite in azimuth:
    cos(phi_jet1 - phi_jet2) < -0.8

  2. Select jet1 with a maximum neutral energy fraction (R_EM1).
    This is our gamma candidate, for which we further require:
    • No charge tracks associated with jet1 (default jet radius is 0.7):
      nChargeTracks_jet1 = 0
      Note, that this charge track veto only works
      in the EEMC region where we do have TPC tracking
    • No barrel towers associated with jet1 (pure EEMC jet):
      nBarrelTowers_jet1 = 0
    • Ratio of the energy in the 3x3 EEMC high tower cluster
      to the total jet energy to be:
      R_cluster>0.99 (previous, softer, cut was 0.9)

     

  3. For the second jet2 (away side jet) we require:
    • That jet2 has at least ~10% of hadronic energy:
      R_EM2<0.9

     

  4. Additional gamma candidate QA requirements:
    • Matching between EEMC SMD uv-strip cluster with a 3x3 cluster of EEMC towers.
      (in addition reject events for which we can not idetify uv-strip intersection)
    • Minimum number of strips in 5-strip EEMC SMD uv-plane clusters to be greater that 3.

Data sample:

  • pp2006(long) - 2006 pp production longitudinal data after applying gamma-jet isolation cuts
    (note the new R_cluster>0.99 cut)

Shower shapes sorted by pre-shower, z-vertex and gamma's eta, phi, pt

Note, that all shapes are normalized at peak to unity

Figure 1:Shower shapes for different detector eta bins

 

Figure 2:Shower shapes for different detector phi bins

 

Figure 3:Shower shapes for different gamma pt bins

 

Figure 4:Shower shapes for different z-vertex bins

 

2008.05.21 EEMC SMD data-driven library: some eta-meson QA plots

Ilya Selyuzhenkov May 21, 2008

EEMC SMD data-driven library: some eta-meson QA plots

Data sample:

  • Subset of 441 eta-meson candidates from Will's analysis.

  • additional QA info (detector eta, pre1, pre2, etc)
    has been added to pi0-tree reader script:
    /star/institutions/iucf/wwjacobs/newEtas_fromPi0finder/ReadEtaTree.C

  • pi0 trees from this RCF directory has been used to regenerate etas NTuple:
    /star/institutions/iucf/wwjacobs/newEtas_fromPi0finder/out_23/

Some observations:

  • eta-meson purity within the invariant mass region [0.5, 0.65] is about 72%

  • Most of the eta-candidates has detector pseudorapidity less or about 1.4,
    what may limits applicability of data-driven shower shapes
    derived from these candidates for higher pseudo-rapidity region,
    where we have most of the background for the gamma-jet
    analysis due to lack of TPC tracking

  • z-vertex distribution is very asymmetric, and peaked around -50cm.
    Only a few candidates has a positive z-vertex values.

Figure 1: Eta-meson invariant mass with signal and background fits and ratio (upper left).
Pseudorapidity [detector and wrt vertex] distributions (right top and bottom plots),
vertex z distributions (bottom left)

 

Figure 2:2D plots for the eta-meson invariant mass vs
azimuthal angle (upper left), pseudorapidity (upper right),
z-vertex (bottom right), and detector pseudorapidity (bottom right)

 

2008.05.27 Shower shapes: pp2006 data, MC gamma-jet and QCD jets, gammas from eta

Ilya Selyuzhenkov May 27, 2008

Shower shapes and triple Gaussian fits for gammas from eta-meson

Figure 1: Shower shapes and triple Gaussian fits for photons from eta-meson
sorted by different conditions of EEMC 1st and 2nd pre-shower layers.
Note: All shapes have been normalized at peak to unity

 

Triple Gaussian fit parameters:
Pre1=0 Pre2=0
0.669864*exp(-0.5*sq((x-0.46016)/0.574864))+0.272997*exp(-0.5*sq((x-0.46016)/-1.84608))+0.0585682*exp(-0.5*sq((x-0.46016)/5.49802))
Pre1=0 Pre2>0
0.0694729*exp(-0.5*sq((x-0.493468)/5.65413))+0.615724*exp(-0.5*sq((x-0.493468)/0.590723))+0.314777*exp(-0.5*sq((x-0.493468)/2.00192))
Pre1>0 Pre2>0
0.0955638*exp(-0.5*sq((x-0.481197)/5.59675))+0.558661*exp(-0.5*sq((x-0.481197)/0.567596))+0.345896*exp(-0.5*sq((x-0.481197)/1.9914))

 

Shower shapes: pp2006, MC gamma-jet and QCD jets, gammas from eta

Shower shapes comparison between different data sets:

  • gammas from eta-meson decay. Obtained from Will's eta-meson analysis
  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Some observations:

  • Shapes for gammas from eta-meson decay
    are in a good agreement with those from MC gamma-jet sample
    (compare red squares with blue triangle in Fig. 2 and 3).

    MC gamma-jet shapes obtained by running a full gamma-jet reconstruction algorithm,
    and this agreement indicates that we are able to reconstruct gamma shapes
    which we put in with data-driven shower shape library.

  • MC gamma-jet shapes match pp2006 data shapes
    for pre1=0 condition, where we expect to be very efficient in background rejection
    (compare red squares with black circles in upper plots of Fig. 2 and 3).

    This indicates that we are able to reproduce EEMC SMD of direct photons with data-driven Monte-Carlo.

  • There is no match between Monte-Carlo QCD background jets and pp2006 data
    for the case when both pre-shower layer fired (pre1>0 and pre2>0).
    (compare green triangles with black circes in bottom right plots of Fig.2 and 3).
    This is the region where we know background dominates our gamma-jet candidates.

    This shows that we still do not reproduce SMD response for our background events
    in our data-driven Monte-Carlo simulations
    (note, that in Monte-Carlo we replace SMD response with real shapes for all background photons
    the same way we do it for direct gammas).

Figure 2: Shower shapes comparison between different data sets.
Shapes for gamma-jet candidates obtained with the same gamma-jet reconstruction algorithm
for three different data samples (pp2006, gamma-jet and QCD jets MC).
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 3:Same as Fig. 2, but with no cuts on gamma and jet pt.
All shapes are similar to those in Fig. 2 with an additional pt cuts.
Note, that blue triangles are the same as in Fig. 2.

 

2008.05.30 Eta, phi, and pt distributions for gamma and jet from MC and pp2006 data

Ilya Selyuzhenkov May 30, 2008

Three data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Figure 1: Gamma eta distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 2: Gamma pt distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 3: Gamma phi distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 4: Away side jet eta distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 5: Away side jet pt distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 6: Gamma-jet delta pt distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 7: Gamma-jet delta eta distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 8: Gamma-jet delta phi distribution.
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

06 Jun

June 2008 posts

 

2008.06.04 Gamma cluster energy in various EEMC layers: data vs MC

Ilya Selyuzhenkov June 04, 2008

Gamma cluster energy in various EEMC layers: data vs MC

Three data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Figure 1: Gamma candidate EEMC pre-shower 1 energy (3x3 cluster).
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 2: Gamma candidate EEMC pre-shower 2 energy (3x3 cluster).
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 3: Gamma candidate EEMC tower energy (3x3 cluster).
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 4: Gamma candidate EEMC post-shower energy (3x3 cluster).
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 5: Gamma candidate EEMC SMD u-plane energy [5-strip cluster] (Figure for v-plane)
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Difference between total and gamma candidate cluster energy for various EEMC layers

Figure 6: Total minus gamma candidate (3x3 cluster) energy in EEMC pre-shower 1 layer
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 7: Total minus gamma candidate (3x3 cluster) energy in EEMC pre-shower 2 layer
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 8: Total minus gamma candidate (3x3 cluster) energy in EEMC tower
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 9: Total minus gamma candidate (3x3 cluster) energy in EEMC post-shower layer
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

 

Figure 10: Total (sector) energy minus gamma candidate (5-strip cluster) energy in EEMC SMD[u-v] layer
pt cuts of 7GeV for the gamma and of 5 GeV for the away side jet have been applied.

2008.06.09 STAR White paper plots (pt distribution: R_cluster 0.99 and 0.9 cuts)

Ilya Selyuzhenkov June 09, 2008

Gamma pt distribution: data vs MC (R_cluster 0.99 and 0.9 cuts)

Three data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Numerical values for different pt-bins from Fig. 1-2

Figure 1: Gamma pt distribution for R_cluster >0.9.
No energy in both pre-shower layer (left plot), and
No energy in pre-shower1 and non-zero energy in pre-shower2 (right plot)
Same figure for R_cluster>0.99 can be found here

 

Figure 2: Gamma pt distribution for R_cluster >0.9.
No energy in first EEMC pre-shower1 layer (left plot), and
non-zero energy in pre-shower1 (right plot)
For more details (yield, ratios, all pre12 four conditions, etc) see figures 1-3 here.

 

Figure 3: Gamma pt distribution for R_cluster >0.99.
For more details (yield, ratios, all pre12 four conditions, etc) see figures 1-3 here.

2008.06.10 Gamma-jet candidate longitudinal double spin asymmetry

Ilya Selyuzhenkov June 10, 2008

Note: No background subtraction has been done yet

The case of pre-shower1=0 (left plots) roughly has 1:1 signal to background ratio,
while pre-shower1>0 (right plots) have 1:10 ratio (See MC to data comparison for details).

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts,
    plus two additional vertex QA cuts:
    a) |z_vertex| < 100 and
    b) 180 < bbcTimeBin < 300
  • Polarization fill by fill: blue and yellow
  • Relative luminosity by polarization fills and runs: relLumi06_070614.txt.gz
  • Equations used to calculate A_LL from the data: pdf file

Figure 1: Gamma-jet candidate A_LL vs gamma pt.
Figures for related epsilon_LL and 1/Lum scaled by a factor 10^7
(see pdf/html links above for epsilon_LL and 1/Lum definitions)

 

Figure 2: Gamma-jet candidate A_LL vs x_gluon.
Figures for related epsilon_LL and 1/Lum scaled by a factor 10^7

 

Figure 3: Gamma-jet candidate A_LL vs x_quark.
Figures for related epsilon_LL and 1/Lum scaled by a factor 10^7

 

Figure 4: Gamma-jet candidate A_LL vs away side jet pt.
Figures for related epsilon_LL and 1/Lum scaled by a factor 10^7

2008.06.18 Photon-jet reconstruction with the EEMC detector (talk at the STAR Collaboration meeting)

Ilya Selyuzhenkov June 18, 2008

Slides

Photon-jet reconstruction with the EEMC detector - Part 1: pdf or odp

Talk outline (preliminary)

  1. Introduction and motivation
  2. Data samples (pp2006, MC gJet, MC QCD bg)
    and gamma-jet reconstruction algorithm:

  3. Comparing pp2006 with Monte-Carlo simulations scaled to the same luminosity
    (EEMC pre-shower sorting):

  4. EEMC SMD shower shapes from different data samples
    (pp2006 and data-driven Monte-Carlo):

  5. Sided residual plots: pp2006 vs data-driven Monte-Carlo
    (gammas from eta meson: 3 gaussian fits)

  6. Various cuts study:

  7. Some QA plots:

  8. A_LL reconstruction technique:

  9. Work in progress... To do list:

    • Understading MC background and pp2006 data shower shapes discrepancy
    • Implementing sided residual technique with shapes sorted by pre1&2 (eta, sector, etc?)
    • Tuning analysis cuts
    • Quantifying signal to background ratio
    • Background subtraction for A_LL, ...
    • What else?
  10. Talk summary

 

07 Jul

July 2008 posts

 

2008.07.07 Pre-shower1 < 5MeV cut study

Ilya Selyuzhenkov July 07, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Figure 1: Correlation between 3x3 cluster energy in pre-shower2 vs. pre-shower1 layers

 

Figure 1a: Distribution of the 3x3 cluster energy in pre-shower1 layer (zoom in for Epre1<0.03 region)
(pp2006 data vs. MC gamma-jet and QCD events)

 

Figure 2: Shower shapes after pre-shower1 < 5MeV cut.
Shapes are narrower than those without pre1 cut (see Fig. 2)

 

 

Figure 3: Gamma pt distribution with pre-shower1 < 5MeV cut.
Compare with distribution withoud pre-shower1 (Fig. 3)

 

Sided residual (before and after pre-shower1 < 5MeV cut)

Figure 4: Fitted peak vs. maximum sided residual (no pre-shower1 cuts)
Only points for pp2006 data are shown.

 

Figure 5: Fitted peak vs. maximum sided residual (after pre-shower1 < 5MeV cut).
Only points for pp2006 data are shown.
Note that distribution for pre1>0,pre2>0 case are narrower
compared to that in Fig.4 (without pre-shower1 cuts).

 

Figure 6: Distribution of maximum sided residual with pre-shower1 < 5MeV cut.

2008.07.16 Gamma-gamma invariant mass cut study

Ilya Selyuzhenkov July 16, 2008

Three data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

My simple gamma-gamma finder is trying to
find a second peaks (clusters) in each SMD u and v planes,
match u and v plane high strip intersections,
and calculate the invaraint mass from associated tower energies (3x3 cluster)
according to the energy sharing between SMD clusters.

Figure 1: Gamma-gamma invariant mass plot.
Only pp2006 data are shown: black: no pt cuts, red: gamma pt>7GeV and jet pt>5 GeV.
Clear pi0 peak in the [0.1,0.2] invariant mass region.
Same data on the log scale

 

Gamma pt distributions

Figure 2: Gamma pt distribution (no inv mass cuts).

 

Figure 3: Gamma pt distribution (m_invMass<0.11 or no second peak found).
This cut improves signal to background ratio.

 

Figure 4: Gamma pt distribution (m_invMass>0.11).
Mostly background events.

 

Shower shapes

Figure 5: Shower shapes (no pre1 and no invMass cuts).
Good match between shapes in case of no energy in pre-shower1 layer (pre1=0 case).

 

Figure 6: Shower shapes (pre1<5MeV, no invMass cuts).
For pre1&2>0 case shapes getting closer to ech other, but still do not match.

 

Figure 7: Shower shapes (cuts: pre1<5MeV, invMass<0.11 or no second peak found).
Note, the surprising agreement between eta-meson shapes (blue) and data (black).

 

Gamma-gamma invariant mass plots

Figure 8: Invariant mass distribution (MC vs. pp2006 data): no pre1 cut

 

Figure 9: Invariant mass distribution (MC vs. pp2006 data): pre1<5MeV
Left side is the same as in Figure 8

 

Figure 10: Invariant mass distribution (MC vs. pp2006 data): pre1>5MeV
Left side plot is empty, since there is no events with [pre1=0 and pre1>5MeV]

2008.07.22 Photons from eta-meson: library QA

Ilya Selyuzhenkov July 22, 2008

Shower shapes

Figure 1: Shower shapes: no energy cuts, only 12 strips from peak (left u-plane, right v-plane).

Figure 1a: Shower shapes: no energy cuts, 150 strips from peak (left u-plane, right v-plane).

 

Figure 2: Shower shapes Energy>8GeV (left u-plane, right v-plane).

 

Figure 3: Shower shapes Energy<=8GeV (left u-plane, right v-plane).

 

One dimensional distributions

Figure 4: Tower energy.

 

Figure 5: Post-shower energy.

 

Figure 6: Pre-shower1 energy.

 

Figure 7: Pre-shower2 energy.

 

Figure 8: Number of library candidates per sector.

 

Correlation plots

Figure 9: Transverse momentum vs. energy.

 

Figure 10: Distance from center of the detector vs. energy.

 

Figure 11: x:y position.

 

Figure 12: u- vs. v-plane position.

2008.07.29 Shower shape comparison with new dd-library bins

Ilya Selyuzhenkov July 29, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

 

Latest data-driven shower shape replacement library:

  • Four pre-shower bins: pre1,2=0, pre1=0,pre2>0 pre1<4MeV, pre1>=4MeV
  • plus two energy bins (E<8GeV, E>=8GeV)

 

Figure 1: Shower shapes for u-plane [12 strips]
Shower shapes for the library are for the E>8GeV bin.

 

Figure 2: Shower shapes for v-plane [12 strips]

 

Figure 3: Shower shapes for u-plane [expanded to 40 strips]

 

Figure 4: Shower shapes for v-plane [expanded to 40 strips]

 

08 Aug

August 2008 posts

 

2008.08.14 Shower shape with bug fixed dd-library

Ilya Selyuzhenkov August 14, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

 

Data-driven maker with bug fixed multi-shape replacement:

  • Four pre-shower bins: pre1,2=0, pre1=0,pre2>0 pre1<4MeV, pre1>=4MeV
  • plus two energy bins (E<8GeV, E>=8GeV)

 

Figure 1: Shower shapes for u-plane [12 strips]
Shower shapes for the library are for the E>8GeV bin.
Open squares and triangles represents raw [without dd-maker]
MC gamma-jet and QCD background shower shapes respectively

 

Figure 2: Shower shapes for v-plane [12 strips]

 

Figure 3: Shower shapes for u-plane [expanded to 40 strips]
Dashed red and green lines represents raw [without dd-maker]
MC gamma-jet and QCD background shower shapes respectively

 

Figure 4: Shower shapes for v-plane [expanded to 40 strips]

 

2008.08.19 Shower shape from pp2008 vs pp2006 data

Ilya Selyuzhenkov August 19, 2008

Data sets:

  • pp2006 - STAR 2006 ppProductionLong data (~ 3.164 pb^1)
    "eemc-http-mb-l2gamma" trigger after applying gamma-jet isolation cuts.
  • pp2008 - STAR ppProduction2008 (~ 5.9M events)
    "fmsslow" trigger after applying gamma-jet isolation cuts.
    [Only ~13 candidates has been selected before pt-cuts]
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Note: Due to lack of statistics for 2008 data, no pt cuts applied on gamma-jet candidates for both 2006 and 2008 date.

Figure 1: Shower shapes for u-plane [pp2006 data: eemc-http-mb-l2gamma trigger]

 

Figure 2: Shower shapes for v-plane [pp2006 data: eemc-http-mb-l2gamma trigger]

 

Figure 3: Shower shapes for u-plane [pp2008 data: fmsslow trigger]

 

Figure 4: Shower shapes for v-plane [pp2008 data: fmsslow trigger]

 

2008.08.25 di-jets from pp2008 vs pp2006 data

Ilya Selyuzhenkov August 25, 2008

Data sets:

  • pp2006 - ppProductionLong [triggerId:137213] (day 136 only)
  • pp2008 - ppProduction2008 [triggerId:220520] (Jan's set of MuDst from day 047)

Event selection:

  • Run jet finder and select only di-jet events [adopt jet-finder script from Murad's analysis]
  • Define jet1 as the jet with largest neutral energy fraction (NEF), and jet2 - the jet with a smaller NEF
  • Require no EEMC towers associated with jet1
  • Select trigger (see above) and require vertex to be found

Figure 1: Vertex z distribution (left: pp2008; right: 2006 data)

Figure 2: eta vs. phi distribution for the jet1 (jet with largest NEF) .

Figure 3: eta vs. z-vertex distribution for the jet1 (jet with largest NEF) .

Figure 4: eta vs. z-vertex distribution for the second jet.

Figure 5: Transverse momentum distribution for jet1.

Figure 6: Number of barrel towers associated with jet1.

Figure 7: Number of charge tracks associated with jet1.

2008.08.26 Shower shape: more constrains for pre1>4E-3 bin

Ilya Selyuzhenkov August 26, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

 

Data-driven library:

  • Four pre-shower bins: pre1,2=0, pre1=0,pre2>0 pre1<4MeV, pre1>=4MeV
  • plus two energy bins (E<8GeV, E>=8GeV)

 

Figure 1: Pre-shower1 energy distribution for Pre1>4 MeV:
Eta meson library for E>8GeV bin [left] and data vs. MC results [right].

 

Figure 2: Shower shapes for v-plane [Pre1<10MeV cut]

Figure 3: Shower shapes for u-plane [Pre1<10MeV cut]

Maximum side residual plots

Definitions for side residual plot (F_peak, F_tal, D_tail) can be found here
For a moment same 3-gaussian shape is used to fit SMD response for all pre-shower bins.
Algo needs to be updated with a new shapes sorted by pre-shower bins.

Figure 4: Sided residual plot for pp2006 data only [Pre1<10MeV cut]

Figure 5: Sided residual projection on "Fitted Peak" axis [Pre1<10MeV cut]

Figure 6: Sided residual projection on "tail difference" axis [Pre1<10MeV cut]

2008.08.27 Gamma-jet candidates detector position for different pre-shower conditions

Ilya Selyuzhenkov August 27, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Figure 1: High u vs. v strip id distribution for different pre-shower conditions.
Left column: QCD jets, middle column: gamma-jet, right columnt: pp2006 data

Figure 2: x vs. y position of the gamma-candidate within EEMC detector
for different pre-shower conditions.
Left column: QCD jets, middle column: gamma-jet, right columnt: pp2006 data

Figure 3:Reconstructed vs. generated (from geant record) gamma pt for the MC gamma-jet sample.
Pre-shower1<10MeV cut applied.

Figure 4:Reconstructed vs. generated (from geant record) gamma eta for the MC gamma-jet sample.
Pre-shower1<10MeV cut applied.

Figure 5:Reconstructed vs. generated (from geant record) gamma phi for the MC gamma-jet sample.
Pre-shower1<10MeV cut applied.

09 Sep

September 2008 posts

 

2008.09.02 Shower shape fits

Ilya Selyuzhenkov September 02, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Shower shape fitting procedure:

  1. Fit with single Gaussian shape using 3 highest strips
  2. Fit with double Gaussian using 5 strips from each side of the peak [11 strips total]
    First Gaussian parameters are fixed from the step above
  3. Re-fit with double Gaussian with initial parameters from step 2 above
  4. Fit with triple Gaussian [fit range varies from 9 to 15 strips, default is 12 strips, see below]
    Initial parameters for the first two Gaussian are fixed from step 3 above
  5. Fit with triple Gaussian with initial parameters from step 4 above
    (releasing all parameters except mean values)

Fitting function "[0]*(exp ( -0.5*((x-[1])/[2])**2 )+[3]*exp ( -0.5*((x-[4])/[5])**2 )+[6]*exp ( -0.5*((x-[7])/[8])**2 ))"

Fit results for MC gamma-jet data sample

Figure 1: MC gamma-jet shower shapes and fits for u-plane
Results from single, double and triple Gaussian fits (using from 9 to 15 strips) are shown.

Figure 2: Same as figure 1. but from v-plane

Figure 3: MC gamma-jet results using triple Gaussian fits within 12 strips from a peak.
Left: u-plane. Right: v-plane

Figure 4: Combined fit results from MC gamma-jet sample

Figure 5: Fitting parameters [see equation for the fit function above].
Note, that parameters 1, 4, and 7 (peak position) has the same value.

Numerical fit results:

  1. pre1=0 pre2=0 [u]: 0.602039*((exp(-0.5*sq((x-0.491324)/0.605927))+(0.578161*exp(-0.5*sq((x-0.491324)/2.05454))))+(0.0937517*exp(-0.5*sq((x-0.491324)/6.37656))))
  2. pre1=0 pre2=0 [v]: 0.729744*((exp(-0.5*sq((x-0.480945)/0.621631))+(0.327792*exp(-0.5*sq((x-0.480945)/2.01717))))+(0.0410935*exp(-0.5*sq((x-0.480945)/6.49599))))
  3. pre1=0 pre2>0 [u]: 0.725212*((exp(-0.5*sq((x-0.474451)/0.560416))+(0.3332*exp(-0.5*sq((x-0.474451)/1.91957))))+(0.0611053*exp(-0.5*sq((x-0.474451)/5.34357))))
  4. pre1=0 pre2>0 [v]: 0.686446*((exp(-0.5*sq((x-0.536662)/0.650485))+(0.388429*exp(-0.5*sq((x-0.536662)/1.99118))))+(0.0712328*exp(-0.5*sq((x-0.536662)/5.64637))))
  5. 0 <4MeV [u]: 0.612486*((exp(-0.5*sq((x-0.485717)/0.592415))+(0.55846*exp(-0.5*sq((x-0.485717)/1.87214))))+(0.0749598*exp(-0.5*sq((x-0.485717)/6.12462))))
  6. 0 <4MeV [v]: 0.651584*((exp(-0.5*sq((x-0.486876)/0.652023))+(0.450767*exp(-0.5*sq((x-0.486876)/2.07667))))+(0.0864232*exp(-0.5*sq((x-0.486876)/5.84357))))
  7. 4 <10MeV [u]: 0.621905*((exp(-0.5*sq((x-0.496841)/0.632917))+(0.512575*exp(-0.5*sq((x-0.496841)/1.97482))))+(0.0927374*exp(-0.5*sq((x-0.496841)/6.10844))))
  8. 4 <10MeV [v]: 0.634943*((exp(-0.5*sq((x-0.505378)/0.660763))+(0.480929*exp(-0.5*sq((x-0.505378)/2.17312))))+(0.0788037*exp(-0.5*sq((x-0.505378)/6.21667))))

Fit results for pp2006 gamma-jet candidates

Figure 6: Same as Fig. 3, but for gamma-jet candidates from pp2006 data

Figure 7: Same as Fig. 5, but for gamma-jet candidates from pp2006 data

2008.09.09 Maximum sided residual with shower shapes sorted by uv- and pre-shower bins

Ilya Selyuzhenkov September 09, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Procedure to calculate maximum sided residual:

  1. For each event fit SMD u and v energy distributions with
    triple Gaussian functions from shower shapes analysis:

    [0]*(exp(-0.5*((x-[1])/[2])**2)+[3]*exp(-0.5*((x-[1])/[4])**2)+[6]*exp(-0.5*((x-[1])/[5])**2))

    Fit parameters sorted by various pre-shower conditions and u and v-planes can be found here
    There are only two free parameters in a final fit: overall amplitude [0] and mean value [1]
    Fit range is +-2 strips from the high strip (5 strips total).

  2. Integrate energy from a fit within +-2 strips from high strip.
    This is our peak energy from fit, F_peak.

  3. Calculate tail energies on left and right sides from the peak for both data, D_tail, and fit, F_tail.
    Tails are integrated up to 30 strips excluding 5 highest strips.
    Determine maximum difference between D_tail and F_tail:
    max(D_tail-F_tail). This is our maximum sided residual.

  4. Plot F_peak vs. max(D_tail-F_tail). This is sided residual plot.

  5. (implementation for this item is in progress)
    Based on MC gamma-jet sided residual plot find a line (some polynomial function)
    which will serve as a cut to separate signal and background.
    Use that cut line to calculate signal to background ratio
    and apply it for the real data analysis.

Figure 1: Maximum sided residual plots for different data sets and various pre-shower condition.
Columns [data sets]: 1. MC QCD background; 2. gamma-jet; 3. pp2006 data
Rows [pre-shower bins]: 1. pre1=0 pre2=0; 2. pre1=0, pre2>0; 3. 0<pre1<4MeV; 4. 4<pre1<10MeV
Results from u and v plane are combined as [U+V]/2

Figure 2: max(D_tail-F_tail) distribution (projection on horizontal axis from Fig.1)
Some observations:
Results for pp2006 and MC gamma-jet are consistent for pre1=0 pre2=0 case (upper left plot)
Results for pp2006 and MC QCD background jets are also in agrees for pre1>0 case (lower left and right plots)

Figure 3: F_peak distribution (projection on vertical axis from Fig.1)

2008.09.16 QA plots for maximum sided residual (obsolete)

Ilya Selyuzhenkov September 16, 2008

These results are obsolete.
Please use this link instead

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Notations used in the plots:

  • Fit peak energy:
    F_peak - integral within +-2 strips from maximum strip
    Maximum strip determined by fitting procedure.
    Float value converted ("cutted") to integer value.
  • Data peak energy:
    D_peak - energy sum within +-2 strips from maximum strip (the same strip Id as for F_peak).
  • Data tails:
    D_tail^left and D_tail^right.
    Energy sum from 3rd strip up to 30 strips on the
    left and right sides from maximum strip (excludes strips which contributes to D_peak)
  • Fit tails:
    F_tail^left and F_tail^right.
    Same definition as for D_tail, but integrals are calculated from a fit function.
  • Maximum sided residual:
    max(D_tail-F_tail)
    Maximum of the data minus fit energy on the left and right sides from the peak.

Figure 1: D_peak from [U+V]/2.

Figure 2: U/V asymmetry for D_peak: [U-V]/[U+V]

Figure 3: F_peak from [U+V]/2.

Figure 4: U/V asymmetry for F_peak: [U-V]/[U+V]

Figure 5: (D_peak - F_peak)/D_peak asymmetry

Figure 6: Maximum sided residual from V vs. U plane.

Figure 7: (D_tail-F_tail)^right vs. (D_tail-F_tail)^left

2008.09.23 QA plots for maximum sided residual (bug fixed update)

Ilya Selyuzhenkov September 23, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    after applying gamma-jet isolation cuts (note: R_cluster > 0.9 is used below).
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Notations used in the plots:

  • Fit peak energy:
    F_peak - integral within +-2 strips from maximum strip
    Maximum strip determined by fitting procedure.
    Float value converted ("cutted") to integer value.
  • Data peak energy:
    D_peak - energy sum within +-2 strips from maximum strip (the same strip Id as for F_peak).
  • Data tails:
    D_tail^left and D_tail^right.
    Energy sum from 3rd strip up to 30 strips on the
    left and right sides from maximum strip (excludes strips which contributes to D_peak)
  • Fit tails:
    F_tail^left and F_tail^right.
    Same definition as for D_tail, but integrals are calculated from a fit function.
  • Maximum sided residual:
    max(D_tail-F_tail)
    Maximum of the data minus fit energy on the left and right sides from the peak.

Figure 1: D_peak from [U+V]/2.

Figure 2: (D_peak - F_peak)/D_peak asymmetry

Figure 3: Maximum sided residual from V vs. U plane.

Figure 4: (D_tail-F_tail)^right. (D_tail-F_tail)^left

2008.09.23 Right-left SMD tail asymmetries

Ilya Selyuzhenkov September 23, 2008

Figure 1: D_peak vs. [right-left] D_tail

Figure 2: [right-left]/[right-+left] D_tail

2008.09.23 Sided residual plot projection: toward s/b efficency/rejection plot

Ilya Selyuzhenkov September 23, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    after applying gamma-jet isolation cuts (note: R_cluster > 0.9 is used below).
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Notations used in the plots:

  • Fit peak energy:
    F_peak - integral within +-2 strips from maximum strip
    Maximum strip determined by fitting procedure.
    Float value converted ("cutted") to integer value.
  • Data peak energy:
    D_peak - energy sum within +-2 strips from maximum strip (the same strip Id as for F_peak).
  • Data tails:
    D_tail^left and D_tail^right.
    Energy sum from 3rd strip up to 30 strips on the
    left and right sides from maximum strip (excludes strips which contributes to D_peak)
  • Fit tails:
    F_tail^left and F_tail^right.
    Same definition as for D_tail, but integrals are calculated from a fit function.
  • Maximum sided residual:
    max(D_tail-F_tail)
    Maximum of the data minus fit energy on the left and right sides from the peak.

Maximum sided residual: MC vs. data comparison

Figure 1: Maximum sided residual plot
Top get more statistics for MC QCD sample plot is redone with a softer R_cluster > 0.9 cut

Figure 2: D_peak (projection on vertical axis for Fig. 1)
Upper left plot (no pre-shower fired case) reveals some difference
between MC gamma-jet and pp2006 data at lower D_peak values.
This difference could be due to background contribution at low energies.
Still needs more statistics for MC QCD jet sample to confirm that statement.

Figure 3: max(D_tail-F_tail) (projection on horisontal axis for Fig. 1)
One can get an idea of signal/background separation (red vs. black) depending on pre-shower condition.

Figure 4: Mean < max(D_tail-F_tail) > vs. D_peak (profile on vertical axis from Fig. 1)
For gamma-jet sample average sided residual is independent on D_peak energy
and has a slight positive shift for all pre-shower>0 conditions.
For large D_peak values (D_peak>0.16) MC gamma-jet and pp2006 data results are getting close to each other.
This corresponds to higher energy gammas, where we have a better signal/background ratio,
and thus more real gammas among gamma-jet candidates from pp2006 data.
(Note: legend's color coding is wrong, colors scheme is the same as in Fig. 3)

Figure 5: Mean < D_peak > vs. max(D_tail-F_tail) (profile on horisontal axis from Fig. 1)
For "no-preshower fired" case MC gamma-jet sample has a large average values than that from pp2006 data.
This reflects the same difference between pp2006 and MC gamma-jet sample at small D_peak values (see Fig. 2, upper left plot).
(Note: legend's color coding is wrong, colors scheme is the same as in Fig. 3)

Figure 6: D_peak vs. gamma pt

Figure 7: D_peak vs. gamma 3x3 tower cluster energy

Figure 8: 3x3 cluster tower energy distribution

Figure 9: Gamma pt distribution

Signal/background separation

The simplest way to get signal/background separation is to draw a straight line
on sided residual plot (Fig. 1) in such a way that
it will contains most of the counts (signal) on the left side,
and use a distance to that line for both MC and pp2006 data samples
as a discriminant for signal/background separation.
To get the distance to the straight line one can rotate sided residual plot
by the angle which corresponds to the slope of this line,
and then project it on "rotated" max(D_tail-F_tail) axis.

Figure 10: Shows "rotated" sided residual plot by "5/6*(pi/2)" angle (this angle has been picked by eye).
One can see that now most of the counts for gamma-jet sample (middle column)
are on the left side from vertical axis.

Figure 11: "Rotated" max(D_tail-F_tail) [projection on horizontal axis for Fig. 10]
Cut on "Rotated" max(D_tail-F_tail) can be used for signal/background separation.
From figure below one can see much better signal/background separation than in Fig. 3

Figure 12: "Rotated" D_peak [projection on vertical axis for Fig. 10]

Optimizing the shape of s/bg separation line

Ideally, instead of straight line one needs to use
an actual shape of side residual distribution for MC gamma-jet sample.
This shape can be extracted and parametrized by the following procedure:

  1. Get slices from sided residual plot for different D_peak values
  2. From each slice get max(D_tail-F_tail) value
    for which most of the counts appears on its left side (for example 80%),
  3. Fit these set of points {D_peak slice, max(D_tail-F_tail)} with a polynomial function

The distance to that polynomial function can be used to determine our signal/background rejection efficiency.

This work is in progress...
Just last one figure showing shapes for 6 slices from sided plot.

Figure 13: max(D_tail-F_tail) for different slices in D_peak (scaled by the integral for each slice)

2008.09.30 Sided residual: purity, efficiency, and background rejection

Ilya Selyuzhenkov September 30, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    after applying gamma-jet isolation cuts (note: R_cluster > 0.9 is used below).
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Notations used in the plots:

  • Fit peak energy:
    F_peak - integral within +-2 strips from maximum strip
    Maximum strip determined by fitting procedure.
    Float value converted ("cutted") to integer value.
  • Data peak energy:
    D_peak - energy sum within +-2 strips from maximum strip (the same strip Id as for F_peak).
  • Data tails:
    D_tail^left and D_tail^right.
    Energy sum from 3rd strip up to 30 strips on the
    left and right sides from maximum strip (excludes strips which contributes to D_peak)
  • Fit tails:
    F_tail^left and F_tail^right.
    Same definition as for D_tail, but integrals are calculated from a fit function.
  • Maximum sided residual:
    max(D_tail-F_tail)
    Maximum of the data minus fit energy on the left and right sides from the peak.

Determining cut line based on sided residual plot

Figure 1: Sided residual plot: D_peak vs. max(D_tail-F_tail)
Red lines show 4th order polynomial functions, a*x^4,
which have 80% of MC gamma-jet counts on the left side.
These lines are obtained independently for each of pre-shower condition
based on fit procedure shown in Fig. 3 below.

Figure 2: max(D_tail-F_tail) distribution
(projection on horizontal axis from sided residual plot, see Fig. 1 above)

Figure 3: max(D_tail-F_tail) [at 80%] vs. D_peak.
For each slice (bin) in D_peak variable, the max(D_tail-F_tail) value
which has 80% of gamma-jet candidates on the left side are plotted.

Lines represent fits to MC gamma-jet points (shown in red) using different fit functions
(linear, 2nd, 4th order polynomials: see legend for color coding).
Note, that in this plot D_peak values are shown on horizontal axis.
Consequently, to get 2nd order polynomial fit on sided residual plot (Fig. 1),
one needs to use sqrt(D_peak) function.
The same apply to 4th order polynomial function.

Figure 4: D_peak vs. horisontal distance from 4th order polinomial function to max(D_tail-F_tail) values.
(compare with Fig. 1: Now 80% of MC gamma-jet counts are on the left side from vertical axis)

Figure 5: Horizontal distance from 4th order polynomial function to max(D_tail-F_tail)
[Projection on horizontal axis from Fig. 4]
Based on this plot one can obtain purity, efficiency, and rejection plots (see Fig. 6 below)

Gamma-jet purity, efficiency, and QCD background rejection

Horizontal distance plotted in Fig. 5 can be used as a cut
separating gamma-jet signal and QCD-jets background,
and for each value of this distance one can define
gamma-jet purity, efficiency, and QCD-background rejection:

  • gamma-jet purity is defined as the ratio of
    the integral on the left for MC gamma-jet data sample, N[g-jet]_left,
    to the sum of the integrals on the left for MC gamma-jet and QCD jets, N[QCD]_left, data samples:
    Purity[gamma-jet] = N[g-jet]_left/(N[g-jet]_left+N[QCD]_left)

  • gamma-jet efficiency is defined as the ratio of
    the integral on the left side for MC gamma-jet data sample, N[g-jet]_left,
    to the total integral for MC gamma-jet data sample, N[g-jet]:
    Efficiency[gamma-jet] = N[g-jet]_left/N[g-jet]

  • QCD background rejection is defined as the ratio of
    the integral on the right side for MC QCD jets data sample, N[QCD]_right,
    to the total integral for MC QCD jets data sample, N[QCD]:
    Rejection[QCD] = N[QCD]_right/N[QCD]

Figure 6: Shows:
purity[g-jet] vs. efficiency[g-jet] (upper left);
rejection[QCD] vs. efficiency[g-jet] (upper right);
purity[g-jet] vs. rejection[QCD] (lower left);
pp2006 to MC ratio, N[pp2006]/(N[g-jet]+N[QCD]), vs. horizontal distance from Fig. 5 (lower right)

10 Oct

October 2008 posts

 

2008.10.13 Jet trees for Michael's gamma filtered events

Ilya Selyuzhenkov October 13, 2008

I have finished production of jet trees for Michael's gamma filtered events

You can find jet and skim file lists in my directory at IUCF disk (RCF):

  • Jet trees: /star/institutions/iucf/IlyaSelyuzhenkov/simu/JetTrees/JetTrees.list
  • Skim trees: /star/institutions/iucf/IlyaSelyuzhenkov/simu/JetTrees/SkimTrees.list
  • Log files: /star/institutions/iucf/IlyaSelyuzhenkov/simu/JetTrees/LogFiles.list

Number of jet events is 1284581 (1020 files).
Production size, including archived log files, is 4.0G.

 

The script to run jet finder:

/star/institutions/iucf/IlyaSelyuzhenkov/simu/JetTrees/20081008_gJet/StRoot/macros/RunJetSimuSkimFinder.C

JetFinder and JetMaker code:

/star/institutions/iucf/IlyaSelyuzhenkov/simu/JetTrees/20081008_gJet/StRoot/StJetFinder
/star/institutions/iucf/IlyaSelyuzhenkov/simu/JetTrees/20081008_gJet/StRoot/StJetMaker

For more details see these threads of discussions:

 

2008.10.14 Purity, efficiency, and background rejection: R_cluster > 0.98

Ilya Selyuzhenkov October 14, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    after applying gamma-jet isolation cuts (note: R_cluster > 0.98 is used below).
  • gamma-jet - data-driven Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
  • QCD jets - data-driven Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Figure 1: Horizontal distance from 4th order polynomial function to max(D_tail-F_tail)
See this page for definition and more details

Figure 2:
purity[g-jet] vs. efficiency[g-jet] (upper left);
rejection[QCD] vs. efficiency[g-jet] (upper right);
purity[g-jet] vs. rejection[QCD] (lower left);
pp2006 to MC ratio, N[pp2006]/(N[g-jet]+N[QCD]), vs. horizontal distance (lower right)

2008.10.15 Comparison of gamma-jets from Michael's filtered events vs. old MC samples

Ilya Selyuzhenkov October 15, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    after applying gamma-jet isolation cuts (note: R_cluster > 0.9 is used below).
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • gamma-jet [old] - data-driven Pythia gamma-jet sample (~170K events).
    Partonic pt range 5-35 GeV.
    Details on jet trees production for Michael's gamma filtered events can be found here.
  • QCD jets [old] - data-driven Pythia QCD jets sample (~4M events).
    Partonic pt range 3-65 GeV.

Some observations:

  • Both Fig. 1a vs. Fig. 1b shows good statistics for old and new (gamma-filtered) MC gamma-jet samples
  • Fig. 1c shows poor statistics for QCD background sample
    within partonic pt range 5-10GeV (only 3 counts for "pre1=0 & pre2=0" condition).
    Fig. 1d (new QCD sample) has much more counts in the same region,
    but it is still only 20-25 entries for the case when
    none of EEMC pre-shower layers fired (upper left corner - our purest gamma-jet sample).
    This may be still insufficient for a various cuts systematic study.
  • Fig. 2 and Fig. 3 shows nice agreement between data and MC
    for both old and new (gamma-filtered) MC samples.
    For pre-shower1>0 case this agreement persists across full range of gamma's pt (7GeV and above).
    Upper plots in Fig. 3 shows some difference between data and Monte-Carlo,
    what could be effect from l2gamma trigger,
    which has not been yet applied for MC events.

Figure 1a: partonic pt for gamma-jet [old] events
after analysis cuts and partonic pt bin weighting
(Note:Arbitrary absolute scale)

Figure 1b: partonic pt for gamma-jet [gamma-filtered] events after analysis cuts.
Michael's StBetaWeightCalculator has been used to caclulate partonic pt weights

Figure 1c: partonic pt for QCD jets [old] events
after analysis cuts and partonic pt bin weighting
(Note:Arbitrary absolute scale)

Figure 1d: partonic pt for QCD jets [gamma-filtered] events after analysis cuts.
Michael's StBetaWeightCalculator has been used to caclulate partonic pt weights

Figure 2: reconstructed gamma pt: old MC vs. pp2006 data (scaled to the same luminosity)

Figure 3: reconstructed gamma pt: gamma-filtered MC vs. pp2006 data (scaled to the same luminosity)

2008.10.15 Purity vs. efficiency from gamma-filtered events: R_cluster > 0.9 vs. R_cluster > 0.98

Ilya Selyuzhenkov October 15, 2008

Data sets:

Gamma-jet candidates from MC gamma filtered events: R_cluster > 0.9

Figure 1: Horizontal distance from sided residual plot: R_cluster > 0.9
(see Figs. 1-5 from this post for horizontal distance definition)

Figure 2: Purity/efficiency/rejection, and data to MC[gamma-jet+QCD] ratio plots: R_cluster > 0.9
(see text above Fig. 6 from this post for purity, efficiency, and background rejection definition)

 

Gamma-jet candidates from MC gamma filtered events: R_cluster > 0.98

Figure 3: Reconstructed gamma pt: R_cluster > 0.98

Figure 4: Horizontal distance from sided residual plot: R_cluster > 0.98

Figure 5: Purity/efficiency/rejection, and data to MC[gamma-jet+QCD] ratio plots: R_cluster > 0.98

2008.10.21 Shower shapes, 5/25 strips cluster energy, raw vs. data-driven MC

Ilya Selyuzhenkov October 21, 2008

Data sets:

Some comments:

  • Overall comment: effect of data-driven shower shape replacement procedure
    on QCD background events is small, except probably pre1=0 pre2=0 case.
  • Fig. 1-3, upper left plots (pre1=0 pre2=0) show that
    average energy per strip in data-driven gamma-jet MC (i.e. solid red square in Fig. 3)
    is systematically higher than that for pp2006 data (black circles in Fig. 3).

    Note, that there is an agreement between SMD shower shapes
    for pp2006 data and data-driven gamma-jet simulations
    if one scales them to the same peak value
    (Compare red vs. black in upper left plot from Fig. 1 at this link)

  • Fig. 4, upper left plot (pre1=0 pre2=0):
    Integrated SMD energy from 25 strips
    in raw gamma-jet simulations (red line) match pp2006 data (black line)
    in the region where signal to background ratio is high, E_smd(25-strips)>0.1GeV.
    This indicates that raw MC does a good job in
    reproducing total energy deposited by direct photon.

  • Fig. 5, upper left plot (pre1=0 pre2=0):
    There is mismatch between distributions of energy in 25 strips cluster
    from data-driven gamma-jet simulations and pp2006 data.
    This probably reflects the way we scale our library shower shapes
    in data-driven shower shape replacement procedure.
    Currently, the scaling factor for the library shape is calculated based on the ratio
    of direct photon energy from Geant record to the energy of the library photon.
    Our library is build out of photons from eta-meson decay,
    which has been reconstructed by running pi0 finder.
    The purity of the library is about 70% (see Fig. 1 at this post for more details).

    The improvement of scaling procedure could be to
    preserve total SMD energy deposited within 25 strips from raw MC,
    and use that energy to scale shower shapes from the library.

  • Fig. 6, upper left plot (pre1=0 pre2=0):
    Mismatch between integrated 5-strip energy for raw MC and pp2006 in Fig. 6
    corresponds to "known" difference in shower shapes from raw Monte-Carlo and real data.

Figure 1: SMD shower shapes: data, raw, and data-driven MC (40 strips).
Vertical axis shows average energy per strip (no overall shower shapes scaling)

Figure 2: Shower shapes: data, raw, and data-driven MC (12 strips)

Figure 3: Shower shapes: data, raw, and data-driven MC (5 strips)

Figure 4: 25 strips SMD cluster energy for raw Monte-Carlo
(Note: type in x-axis lables, should be "25 strip peak" instead of 5)

Figure 5: 25 strips SMD cluster energy for data-driven Monte-Carlo

Figure 6: 5 strips SMD peak energy for raw Monte-Carlo

Figure 7: 5 strips SMD peak energy for data-driven Monte-Carlo

Figure 8:Energy from the right tail (up to 30 strips) for raw Monte-Carlo

Figure 9:Energy from the right tail (up to 30 strips) for data-driven Monte-Carlo

2008.10.27 SMD-based shower shape scaling: 25 strips cluster energy, raw vs. data-driven MC

Ilya Selyuzhenkov October 27, 2008

Data sets:

Shower shapes scaling options in data-driven maker:

  1. scale = E_smd^geant / E_smd^library (default)
    E_smd^geant is SMD energy associated with given photon
    integrated over +/- 12 strips from raw Monte-Carlo,
    and E_smd^library is SMD energy from +/- 12 strips for the library photon.
  2. scale = E_Geant / E_library (used before in all posts)
    E_Geant is thrown photon energy from Geant record,
    and E_library is stand for energy of the library photon.

 

In all figures below (exept for pp2006 data and raw Monte-Carlo)
the SMD based shower shape scaling has been used.

Figure 1: SMD shower shapes: data, raw, and data-driven MC (40 strips).
Vertical axis shows average energy per strip (no overall shower shapes scaling)

Figure 2: Shower shapes: data, raw, and data-driven MC (12 strips)

Figure 3: Shower shapes: data, raw, and data-driven MC (5 strips)

Figure 4: 25 strips SMD cluster energy for data-driven Monte-Carlo
(SMD based shower shape scaling)

Figure 5: 25 strips SMD cluster energy for raw Monte-Carlo
Note, the difference between results in Fig. 4 and 5. for MC gamma-jets (shown in red)
at low energy (Esmd < 0.04) for pre1=0 pre2=0 case.
This effect is due to the "Number of strips fired in 5-strips cluster > 3" cut.
In data-driven Monte-Carlo we may have shower shapes
with small number of strips fired (rejected in raw Monte-Carlo)
to be replaced by library shape with different (bigger) number of strips fired.
This mostly affects photons which starts to shower
later in the detector and only fires few strips (pre1=0 pre2=0 case)

2008.10.30 Various cuts study (pt, Esmd, 8 strips replaced)

Ilya Selyuzhenkov October 30, 2008

Below are links to drupal pages
with various SMD energy distributions and shower shapes
for the following set of cuts/conditions:

  • Case A: pt > 7 GeV, +/- 12 strips replaced
  • Case B: pt > 7 GeV, +/- 8 strips replaced
  • Case C: pt > 7 GeV, +/- 12 strips replaced, E_smd(25strips) > 0.1
  • Case D: pt > 8.5 GeV, +/- 12 strips replaced

 

2008.10.30 Distance to cut line from sided residual

Figure 1: Case A

Figure 2:Case B

Figure 3:Case C

Figure 4:Case D

2008.10.30 SMD shower shapes: data, raw, and data-driven MC (12 strips)

Figure 1: Case A

Figure 2:Case B

Figure 3:Case C

Figure 4:Case D

2008.10.30 SMD shower shapes: data, raw, and data-driven MC (30 strips)

Figure 1: Case A

Figure 2: Case B

Figure 3: Case C

Figure 4: Case D

2008.10.30 Sided residual

Figure 1: Case A

Figure 2:Case B

Figure 3:Case C

Figure 4:Case D

2008.10.30 Smd emergy for left tail (-3 to -30 strips)

Figure 1: Case A

Figure 2:Case B

Figure 3:Case C

Figure 4:Case D

2008.10.30 Smd emergy for right tail (3 to 30 strips)

Figure 1: Case A

Figure 2:Case B

Figure 3:Case C

Figure 4:Case D

2008.10.30 Smd energy for 25 central strips

Figure 1: Case A

Figure 2:Case B

Figure 3:Case C

Figure 4:Case D

2008.10.30 Smd energy for 5 central strips

Figure 1: Case A

Figure 2:Case B

Figure 3:Case C

Figure 4:Case D

11 Nov

November 2008 posts

 

2008.11.06 Gamma-jet reconstruction with the Endcap EMC (Analysis status update)

Ilya Selyuzhenkov November 06, 2008

Gamma-jet reconstruction with the Endcap EMC (Analysis status update for Spin PWG)

 

2008.11.11 Yields vs. analysis cuts

Ilya Selyuzhenkov November 11, 2008

Data sets:

Figure 1: Reconstructed gamma pt for di-jet events and
Geant cuts: pt_gamma[Geant] > 7GeV and 1.05 < eta_gamma[Geant] < 2.0
Total integral for the histogram is: N_total = 5284
(after weighting different partonic pt bins and scaled to 3.164pb^-1).
Compare with number from Jim Sowinski study for
Endcap East+West gamma-jet and pt>7 GeV: N_Jim = 5472
( Jim's numbers are scaled to 3.164pb^-1 : [2539+5936]*3.164/4.9)

Figure 2: Reconstructed jet pt for di-jet events and the same cuts as in Fig. 1

Yield vs. various analysis cuts

List of cuts (sorted by bin number in Figs. 2 and 3):

  1. N_events : total number of di-jet events found by the jet-finder
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_{3x3cluster} > 0.9 : Energy in 3x3 cluster of EEMC tower to the total jet energy
  4. R_EM^jet < 0.9 : neutral energy fraction cut for on away side jet
  5. N_ch=0 : no charge tracks associated with a gamma candidate
  6. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  7. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  8. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  9. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  10. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster

Figure 3: Number of accepted events vs. various analysis cuts
The starting number of events (shown in first bin of the plots) is
the number of di-jets with reconstructed gamma_pt>7 GeV and jet_pt>5 GeV
upper left: cuts applied independently
upper right: cuts applied sequentially
lower left: ratio of pp2006 data vs. MC sum of gamma-jet and QCD-jets events (cuts applied independently)
lower right:ratio of pp2006 data vs. MC sum of gamma-jet and QCD jets events (cuts applied sequentially)

Figure 4: Number of accepted events vs. various analysis cuts
Data from Fig. 3 (upper plots) scaled to the initial number of events from first bin:
left: cuts applied independently
right: cuts applied sequentially

2008.11.18 Cluster isolation cuts: 2x1 vs. 2x2 vs. 3x3

Ilya Selyuzhenkov November 18, 2008

Data sets:

2x1, 2x2, and 3x3 clusters definition:

  • 3x3 cluster: tower energy sum for 3x3 patch around highest tower
  • 2x2 cluster: tower energy sum for 2x2 patch
    which are closest to 3x3 tower patch centroid.
    3x3 tower patch centroid is defined based
    on tower energies weighted wrt tower centers:
    centroid = sum{E_tow * r_tow} / sum{E_tow}.
    Here r_tow=(x_tow, y_tow) denotes tower center.
  • 2x1 cluster: tower energy sum for high tower plus second highest tower in 3x3 patch
  • r=0.7 energy is calculated based on towers
    within a radius of 0.7 (in delta phi and eta) from high tower

Cuts applied

all gamma-jet candidate selection cuts except 3x3/r=0.7 energy isolation cut

 

Results for 2x1, 2x2, and 3x3 clusters

  1. Energy fraction in NxN cluster in r=0.7 radius
    2x1, 2x2, 3x3 patch to jet radius of 0.7 energy ratios
  2. Yield vs. NxN cluster energy fraction in r=0.7
    For a given cluster energy fraction yield is defined as an integral on the right
  3. Efficiency vs. NxN cluster energy fraction in r=0.7
    For a given cluster energy fraction
    efficiency is defined as the yield (on the right)
    normalized by the total integral (total yield)

 

Efficiency vs. NxN cluster energy fraction in r=0.7

Efficiency vs. NxN cluster energy fraction in r=0.7

Figure 1b: 2x1/0.7 ratio

Figure 2b: 2x2/0.7 ratio

Figure 3b: 3x3/0.7 ratio

Figure 4b: 3x3/0.7 ratio but only using towers which passed jet finder threshold

Energy fraction in NxN cluster within r=0.7 radius

Energy fraction in NxN cluster within r=0.7 radius

Figure 1a: 2x1/0.7 ratio

Figure 2a: 2x2/0.7 ratio

Figure 3a: 3x3/0.7 ratio

Figure 4a: 3x3/0.7 ratio but only using towers which passed jet finder threshold

Yield vs. NxN cluster energy fraction in r=0.7

Yield vs. NxN cluster energy fraction in r=0.7

Figure 1c: 2x1/0.7 ratio

Figure 2c: 2x2/0.7 ratio

Figure 3c: 3x3/0.7 ratio

Figure 4c: 3x3/0.7 ratio but only using towers which passed jet finder threshold

2008.11.21 Energy fraction from 2x1 vs. 2x2 vs. 3x3 or 0.7 radius: rapidity dependence

Ilya Selyuzhenkov November 21, 2008

Data sets:

2x1, 2x2, and 3x3 clusters definition:

  • 3x3 cluster: tower energy sum for 3x3 patch around highest tower
  • 2x2 cluster: tower energy sum for 2x2 patch
    which are closest to 3x3 tower patch centroid.
    3x3 tower patch centroid is defined based
    on tower energies weighted wrt tower centers:
    centroid = sum{E_tow * r_tow} / sum{E_tow}.
    Here r_tow=(x_tow, y_tow) denotes tower center.
  • 2x1 cluster: tower energy sum for high tower plus second highest tower in 3x3 patch
  • r=0.7 energy is calculated based on towers
    within a radius of 0.7 (in delta phi and eta) from high tower

Cuts applied

all gamma-jet candidate selection cuts except 3x3/r=0.7 energy isolation cut

Results

There are two sets of figures in links below:

  • Number of counts for a given energy fraction
  • Yield above given energy fraction
    [figures with right integral in the caption]

    Yield is defined as the integral above given energy fraction
    up to the maximum value of 1

Gamma candidate detector eta < 1.5
(eta region where we do have most of the TPC tracking):

  1. Cluster energy fraction in 0.7 radius
  2. 2x1 and 2x2 cluster energy fraction in 3x3 patch

Gamma candidate detector eta > 1.5:
(smaller tower size)

  1. Cluster energy fraction in 0.7 radius
  2. 2x1 and 2x2 cluster energy fraction in 3x3 patch

Some observation

  • For pre1>0 condition (contains most of events)
    yield in Monte-Carlo for eta > 1.5 case
    is about factor of two different than that from pp2006 data,
    while for eta < 1.5 Monte-Carlo yield agrees with data within 10-15%.
    This could be due to trigger effect?
  • For pre1=0 case yiled for both eta > 1.5 and eta < 1.5 are different in data and MC
    This could be due to migration of counts from pre1=0 to pre1>0
    in pp2006 data due to more material budget than it is Monte-Carlo
  • For pre1=0 condition pp2006 data shapes are not reproduced by gamma-jet Monte-Carlo.
    With a larger cluster size (2x1 -> 3x3) the pp2006 and MC gamma-jet shapes
    are getting closer to each other.
  • For pre1>0 condition (with statistics available),
    pp2006 data shapes are consistent with QCD Monte-Carlo.

 

Cluster energy fraction in 3x3 patch: detector eta > 1.5

Energy fraction from NxN cluster in 3x3 patch: detector eta > 1.5

Figure 1a: 2x1/3x3 energy fraction [number of counts per given fraction]

Figure 2a: 2x2/3x3 energy fraction [number of counts per given fraction]

Yield vs. NxN cluster energy fraction in 3x3 patch: detector eta > 1.5

Figure 4a: 2x1/3x3 energy fraction [yield]

Figure 5a: 2x2/3x3 energy fraction [yield]

2008.11.25 Yiled vs. analysis cuts: eta dependence

Ilya Selyuzhenkov November 25, 2008

Data sets:

Some observation

  • Fig. 1 [upper&lower left, 3rd bin] indicates that
    cluster energy isolation is the most important cut
    for signal/background separation
  • Fig.1 [lower right, 3rd bin] shows that
    R_cluster cut is independent from (or orthogonal to) other cuts
  • Fig.1 [upper&lower left 4th bin] shows that
    cut on neutral energy fraction for the away side jet
    rejects more signal that background events

    We probably need to reconsider that cut
  • Fig.2 [lower left, 5th bin] shows that
    charge particle veto significantly improves
    signal to background ratio
  • Fig.2 [lower right, 5th bin] shows that
    charge particle veto also independent from other cuts

  • Fig.3 [lower left, 5th bin] shows that
    in the region were we do not have TPC tracking (photon eta > 1.5)
    charge particle veto is not efficient
    ,
    although there is still some improvement from this cut.
    This probably due to tracks with eta <1.5
    which fall into large isolation radius r=0.7.

Yield vs. various analysis cuts

List of cuts (sorted according to bin number in Figs. 1-3. [No SMD sided residual cuts]):

  1. N_events : total number of di-jet events found by the jet-finder
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_{3x3cluster}: Energy in 3x3 cluster of EEMC tower to the total jet energy
    R_{3x3cluster}>0.9 for Fig. 1, and it is disabled in Fig. 2 and 3
  4. R_EM^jet < 0.9 : neutral energy fraction cut for on away side jet
  5. N_ch=0 : no charge tracks associated with a gamma candidate
  6. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  7. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  8. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  9. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  10. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster

Figure 1: Number of accepted events vs. various analysis cuts
The starting number of events (shown in first bin of the plots) is
the number of di-jets with reconstructed gamma_pt>7 GeV and jet_pt>5 GeV
upper left: cuts applied independently
upper right: expept this cut fired
(event passed all other cuts and being rejected by this cut)
lower left: "cuts applied independently" normalized by the total number of events
lower right: "expept this cut fired" normalized by the total number of events

Figure 2: Same as Fig.1 except: no R_cluster cut and photon detector eta < 1.5
(eta region where we do have most of the TPC tracking)

Figure 3: Same as Fig.1 except: no R_cluster cut and photon detector eta > 1.5

12 Dec

December 2008 posts

 

2008.12.08 Run 8 EEMC QA

Ilya Selyuzhenkov December 08, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]
    Days: 53-70; ~0.5M triggered events (1/3 of available statistics)

Detector subsystems involved in analysis:

  1. TPC (vertex, jets, charge particle veto)
  2. Endcap EMC (triggering, photon candidate reconstruction)
  3. Barrel EMC (away side jet reconstruction)

Gamma-jet analysis cuts:

  1. Select only di-jet events
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_EM^jet < 0.9 : neutral energy fraction cut for the away side jet
  4. N_ch=0 : no charge tracks associated with a gamma candidate
  5. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  6. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  7. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  8. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  9. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster
  10. R_{3x3cluster}: Energy in 3x3 cluster of EEMC tower to the total jet energy (not applied here)

Figure 1: EEMC x vs. y position of photon candidate for 2008 data sample
Problem with pre-shower layer in Sector 10 can been seen in the upper left corner

Figure 2: EEMC x vs. y position of photon candidate for 2006 data sample

Figure 3: Average < E_pre1 * E_pre2 > for 3x3 cluster around high tower
vs run number for sectors 9, 10 and 11
Note, zero pre-shower energy for sector 10 (black points) for days 61, 62, 64, and 67.
All di-jet events for pp2008 data are shown (no gamma-jet cuts)

Figure 3a: Same as Fig.3, zoom into day 61

Figure 3b: Same as Fig.3, zoom into day 62
Figure 3c: Same as Fig.3, zoom into day 64
Figure 3d: Same as Fig.3, zoom into day 67

Figure 4: EEMC x vs. y position of photon candidate for 2008 data sample
Same as Fig. 1, but excluding days: 61, 62, 64, and 67

Conclusion on QA:

No problem with pp2008 data have been found,
except that for some runs (mostly on days 61, 62, 64, and 67)
EEMC pre-shower layer for sector 10 was off.

Comparison between 2006 and 2008 data

Figure 5: Vertex z distribution:
All gamma-jet cuts applied, plus pt_gamma>7 and pt_jet > 5 GeV (exlcuding days 61, 62, 64, and 67)
Results are shown for pp2008 data sample (black), vs. pp2006 data (red).
pp2008 data scaled to the same total number of candidates as in pp2006 data.

Figure 6: Shower shapes within +/- 30 strips from high strip (same cuts as in Fig. 5):

Figure 7: Shower shapes within +/- 5 strips from high strip
(same cuts as in Fig. 5, no scaling):

2008.12.09 pp Run 8 vs. Run 6 SMD shower shapes

Ilya Selyuzhenkov December 09, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]
    Days: 53-70; ~0.5M triggered events (1/3 of available statistics)

 

2008.12.09 pp Run 8 vs. Run 6 SMD shower shapes

Ilya Selyuzhenkov December 09, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]
    Days: 53-70; ~0.5M triggered events (1/3 of available statistics)

Gamma-jet analysis cuts:

  1. Select only di-jet events
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_EM^jet < 0.9 : neutral energy fraction cut for the away side jet
  4. N_ch=0 : no charge tracks associated with a gamma candidate
  5. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  6. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  7. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  8. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  9. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster
  10. R_{3x3cluster}: Energy in 3x3 cluster of EEMC tower to the total jet energy (not applied here)

Comparison between 2006 and 2008 data

Figure 1: Vertex z distribution:
All gamma-jet cuts applied, plus pt_gamma>7 and pt_jet > 5 GeV (exlcuding days 61, 62, 64, and 67)
Results are shown for pp2008 data sample (black), vs. pp2006 data (red).
pp2008 data scaled to the same total number of candidates as in pp2006 data.

Figure 2: Shower shapes within +/- 30 strips from high strip (same cuts as in Fig. 1):

Figure 3: Shower shapes within +/- 5 strips from high strip
(same cuts as in Fig. 1, no scaling):

2008.12.09 pp Run 8 vs. Run 6 SMD shower shapes

Ilya Selyuzhenkov December 09, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]
    Days: 53-70; ~0.5M triggered events (1/3 of available statistics)

Gamma-jet analysis cuts:

  1. Select only di-jet events
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_EM^jet < 0.9 : neutral energy fraction cut for the away side jet
  4. N_ch=0 : no charge tracks associated with a gamma candidate
  5. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  6. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  7. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  8. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  9. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster
  10. R_{3x3cluster}: Energy in 3x3 cluster of EEMC tower to the total jet energy (not applied here)

Comparison between 2006 and 2008 data

Figure 1: Vertex z distribution:
All gamma-jet cuts applied, plus pt_gamma>7 and pt_jet > 5 GeV (exlcuding days 61, 62, 64, and 67)
Results are shown for pp2008 data sample (black), vs. pp2006 data (red).
pp2008 data scaled to the same total number of candidates as in pp2006 data.

Figure 2: Shower shapes within +/- 30 strips from high strip (same cuts as in Fig. 1):

Figure 3: Shower shapes within +/- 5 strips from high strip
(same cuts as in Fig. 1, no scaling):

2008.12.09 pp Run 8 vs. Run 6 SMD shower shapes

Ilya Selyuzhenkov December 09, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]
    Days: 53-70; ~0.5M triggered events (1/3 of available statistics)

Gamma-jet analysis cuts:

  1. Select only di-jet events
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_EM^jet < 0.9 : neutral energy fraction cut for the away side jet
  4. N_ch=0 : no charge tracks associated with a gamma candidate
  5. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  6. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  7. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  8. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  9. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster
  10. R_{3x3cluster}: Energy in 3x3 cluster of EEMC tower to the total jet energy (not applied here)

Comparison between 2006 and 2008 data

Figure 1: Vertex z distribution:
All gamma-jet cuts applied, plus pt_gamma>7 and pt_jet > 5 GeV (exlcuding days 61, 62, 64, and 67)
Results are shown for pp2008 data sample (black), vs. pp2006 data (red).
pp2008 data scaled to the same total number of candidates as in pp2006 data.

Figure 2: Shower shapes within +/- 30 strips from high strip (same cuts as in Fig. 1):

Figure 3: Shower shapes within +/- 5 strips from high strip
(same cuts as in Fig. 1, no scaling):

2008.12.09 pp Run 8 vs. Run 6 SMD shower shapes

Ilya Selyuzhenkov December 09, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]
    Days: 53-70; ~0.5M triggered events (1/3 of available statistics)

Gamma-jet analysis cuts:

  1. Select only di-jet events
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_EM^jet < 0.9 : neutral energy fraction cut for the away side jet
  4. N_ch=0 : no charge tracks associated with a gamma candidate
  5. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  6. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  7. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  8. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  9. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster
  10. R_{3x3cluster}: Energy in 3x3 cluster of EEMC tower to the total jet energy (not applied here)

Comparison between 2006 and 2008 data

Figure 1: Vertex z distribution:
All gamma-jet cuts applied, plus pt_gamma>7 and pt_jet > 5 GeV (exlcuding days 61, 62, 64, and 67)
Results are shown for pp2008 data sample (black), vs. pp2006 data (red).
pp2008 data scaled to the same total number of candidates as in pp2006 data.

Figure 2: Shower shapes within +/- 30 strips from high strip (same cuts as in Fig. 1):

Figure 3: Shower shapes within +/- 5 strips from high strip
(same cuts as in Fig. 1, no scaling):

Conclusion:

 

2008.12.09 pp Run 8 vs. Run 6 shower shapes

Ilya Selyuzhenkov December 09, 2008

Data sets:

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]
    Days: 53-70; ~0.5M triggered events (1/3 of available statistics)

Gamma-jet analysis cuts:

  1. Select only di-jet events
  2. cos(phi_gamma - phi_jet) < -0.8 : gamma-jet opposite in phi
  3. R_EM^jet < 0.9 : neutral energy fraction cut for the away side jet
  4. N_ch=0 : no charge tracks associated with a gamma candidate
  5. N_bTow = 0 : no barrel towers associated with a gamma candidate (gamma in the endcap)
  6. N_(5-strip cluster)^u > 2 : minimum number of strips in EEMC SMD u-plane cluster around peak
  7. N_(5-strip cluster)^v > 2 : minimum number of strips in EEMC SMD v-plane cluster around peak
  8. gamma-algo fail : my algorithm failed to match tower with SMD uv-intersection, etc...
  9. Tow:SMD match : SMD uv-intersection has a tower which is not in a 3x3 cluster
  10. R_{3x3cluster}: Energy in 3x3 cluster of EEMC tower to the total jet energy (not applied here)

Comparison between 2006 and 2008 data

Figure 1: Vertex z distribution:
All gamma-jet cuts applied, plus pt_gamma>7 and pt_jet > 5 GeV (exlcuding days 61, 62, 64, and 67)
Results are shown for pp2008 data sample (black), vs. pp2006 data (red).
pp2008 data scaled to the same total number of candidates as in pp2006 data.

Figure 2: Shower shapes within +/- 30 strips from high strip (same cuts as in Fig. 1):

Figure 3: Shower shapes within +/- 5 strips from high strip
(same cuts as in Fig. 1, no scaling):

2008.12.11 Run 8 EEMC QA (presentation for Spin PWG)

Ilya Selyuzhenkov December 11, 2008

Run 8 QA with EEMC gamma-jet candidates

Presentation in pdf or open office file format

2008.12.16 Effect of L2gamma trigger in simulations

Ilya Selyuzhenkov December 16, 2008

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.

Cuts applied

Gamma-jet isolation cuts except 3x3/r=0.7 energy isolation cut

Data driven shower shape replacement maker fix

Figure 1: (reproducing old results with dd-maker fix)
transverse momentum and vertex z distributions
before (with ideal gains/pedestals) and
after (with realistic gains/pedestal tables) dd-maker fix are in a good agreement.
For details on "dd-maker problem", read these hyper news threads:
emc2:2905, emc2:2900, and phana:294
Now we can run L2gamma trigger emulation and Eemc SMD ddMaker
in the same analysis chain.

l2-gamma trigger effect in simulation

Figure 2: Vertex z distribution with and without trigger condition in simulations
(emulated trigger: eemc-http-mb-L2gamma [id:137641]).
Solid red/green symbols show results with l2gamma condition applied,
while red/green lines show results for the same analysis cuts but without trigger condition.
Note, good agreement between MC QCD jets with trigger condition on (green solid squared)
and pp2006 data (black solid circles) for pre-shower1>0 case.

Figure 3: pt distribution with/without trigger condition in simulations.
Same color coding as in Fig. 2

Figure 4: Same as Fig. 3 just on a log scale
One can clearly see large trigger effect when applied for QCD jet events,
and a little effect for direct gammas.

Figure 5: gamma candidate pt QCD (right) and prompt photon (left) Monte-Carlo:
no (upper) with (lower) L2e-gamma trigger condition
No photon pt and no jet pt cuts

Figure 6: gamma candidate pt for QCD Monte-Carlo: no L2e-gamma trigger condition
No photon pt and no jet pt cuts

Figure 7: gamma candidate pt for QCD Monte-Carlo: L2e-gamma trigger condition applied (id:137641)
No photon pt and no jet pt cuts

2008.12.19 Parton pt distribution for Pythia QCD and gamma-jet events

Ilya Selyuzhenkov December 19, 2008

Data sets

Cuts applied

Gamma-jet isolation cuts except 3x3/r=0.7 energy isolation cut

Figure 1: Parton pt distibution for gamma-jet candidates from Pythia QCD sample
with various pt and l2gamma trigger conditions

Figure 2: Parton pt distibution for gamma-jet candidates from Pythia prompt photon sample
with various pt and l2gamma trigger conditions

2009

Year 2009 posts

 

01 Jan

January 2009 posts

 

2009.01.08 Away side jet pt vs. photon pt

Ilya Selyuzhenkov January 08, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered pp2006 events

Comments

(concentrated on pre-shower1>0 case
which has better statistics for QCD Monte-Carlo):

  • Fig.1, lower plots
    Vertex z distributions from QCD MC and pp2006 data are different in the negative region
  • Fig.2, lower plots
    For the away side jet pt < 8GeV region
    QCD Monte-Carlo underestimates the data.
  • Fig.4, lower plots
    gamma-jet pt asymmetry plot shows
    that in QCD MC photon and jet pt's are better correlated than in the data
  • Fig.5, lower plots
    Most of the differences between QCD MC and pp2006 data for pre-shower1>0 case
    are probably from the lower gamma and jet pt region

Figures

Figure 1: Vertex z distribution

Figure 2: Away side jet pt

Figure 3: Photon pt

Figure 4: gamma-jet pt asymmetry: (pt_gamma - pt_jet)/pt_gamma

Figure 5: gamma pt vs. away side jet pt
1st column: triggered pp2006 data
2nd column: gamma-jet MC (l2gamma trigger on)
3rd column: QCD background MC (l2gamma trigger on)

2009.01.20 Away side jet pt vs. photon pt: more stats for QCD pt_parton 9-15GeV

Ilya Selyuzhenkov January 20, 2009

Note:
this is an update with 10x more statitstics for QCD 9-15GeV parton pt bin.
See this post for old results.

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered pp2006 events

Comments

  • Vertex z distributions from QCD MC and pp2006 data
    are different in the negative region (see Fig.1)
  • pp2006 data to Monte-Carlo ratio
    does not depends on reconstructed photon pt,
    but it has some vertex z dependence
    (see data to MC ratio in Fig.6 for pre-shower1 > 4MeV case)

Figures

Figure 1: Vertex z distribution

Figure 2: Away side jet pt

Figure 3: Photon pt

Figure 4: gamma-jet pt asymmetry: (pt_gamma - pt_jet)/pt_gamma

Figure 5: gamma pt vs. away side jet pt
1st column: triggered pp2006 data
2nd column: gamma-jet MC (l2gamma trigger on)
3rd column: QCD background MC (l2gamma trigger on)

Data to Monte_Carlo normalization

Figure 6: pp2006 data to Monte -Carlo sum [QCD + gamma-jet] ratio
for pre-shower1>4MeV (most of statistics)
Left: data to MC ratio vs. reconstructed gamma pt.
Solid line shows constant line fit (p0 ~ 1.3)
Right: data to MC ratio vs. reconstructed vertex position

2009.01.27 gamma and jet pt plots with detector |eta|_jet < 0.8, pt_jet > 7

Ilya Selyuzhenkov January 27, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • jet pt > 7GeV
  • Gamma pt > 7GeV or no pt cuts
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered pp2006 events
  • cos (phi_jet - phi_gamma) < -0.8
  • detector |eta_jet|< 0.8
  • |v_z| < 100

Figures

All figures:

  • All pre-shower conditions combined, pre1<10MeV
  • Left plots: no gamma pt cut
    Right plots: pt_gamma >7GeV
  • Thick blue line shows MC sum: QCD + gamma-jet
  • Thin solid color lines shows distributions from various partonic pt bins for QCD MC
    See figures legend for color coding

Figure 1: Vertex z distribution

Figure 2: Photon eta

Figure 3: Away side jet eta

Figure 4:Photon pt

Figure 5: Away side jet pt

Figure 6: Away side jet detector eta

2009.01.27 gamma and jet pt plots with |eta|_jet < 0.7

Ilya Selyuzhenkov January 27, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV or no pt cuts
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered pp2006 events
  • cos (phi_jet - phi_gamma) < -0.8
  • |eta_jet|< 0.7
  • |v_z| < 100

Figures

All figures:

  • All pre-shower conditions combined, pre1<10MeV
  • Left plots: no gamma pt cut
    Right plots: pt_gamma >7GeV
  • Thick blue line shows MC sum: QCD + gamma-jet
  • Thin solid color lines shows distributions from various partonic pt bins for QCD MC
    See figures legend for color coding

Figure 1: Vertex z distribution

Figure 2: Photon eta

Figure 3: Away side jet eta

Figure 4:Photon pt

Same as in Fig.4 on a log scale: no gamma pt cut and pt>7GeV

Figure 5: Away side jet pt

Same as in Fig.5 on a log scale: no gamma pt cut and pt>7GeV

02 Feb

February 2009 posts

 

2009.02.02 No pre-shower cuts, Normalization fudge factor 1.24

Ilya Selyuzhenkov February 02, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered pp2006 events
  • cos (phi_jet - phi_gamma) < -0.8
  • detector |eta_jet|< 0.8
  • |v_z| < 100

Figures

All figures:

  • All pre-shower conditions combined, No pre-shower cuts
  • Thick blue line shows MC sum: QCD + gamma-jet
  • Black solid circles: pp2006 data
  • Monte-Carlo results first scaled to 3.164 pb^-1 according to Pythia luminosity
    and then an additional fudge factor of 1.24 has been applied.
    Fudge factor is defined as the yields ratio from data to scaled with Pythia luminosity Monte-Carlo
    for pt_jet>7GeV and pt_gamma>7 candidates

Figure 1: Vertex z distribution with pt_jet>7 cut (left) and without pt_jet cut (rigth)

Figure 2: Photon (left) and away side jet (right) pt

Figure 3: Photon detector eta (left) and corrected for vertex eta (right)

Figure 4: Away side jet detector eta (left) and corrected for vertex eta (right)

Figure 5: Preshower 1 (left) and Pre-shower2 (right) energy

2009.02.03 No pre-shower cuts, pt_jet >7 vs. No pt_jet cuts

Ilya Selyuzhenkov February 03, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • gamma-jet[gamma-filtered] - data-driven Prompt Photon [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.
  • QCD jets[gamma-filtered] - data-driven QCD [p6410EemcGammaFilter] events.
    Partonic pt range 2-25 GeV.

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered pp2006 events
  • cos (phi_jet - phi_gamma) < -0.8
  • detector |eta_jet|< 0.8
  • |v_z| < 100

Figures

Each figure has:

  • All pre-shower conditions combined, No pre-shower cuts
  • Thick blue line shows MC sum: QCD + gamma-jet
  • Black solid circles shows pp2006 data
  • Left plots: pt_jet>7GeV
    Right plots: no cuts on pt_jet
  • Monte-Carlo results for QCD and gamma-jet samples are first
    scaled to 3.164 pb^-1 according to Pythia luminosity,
    added together, and then an additional fudge factor of 1.24 applied.
    Fudge factor is defined as pp2006 to Monte-Carlo sum ratio
    for pt_jet>7GeV and pt_gamma>7 candidates

Figure 1: Vertex z distribution

Figure 2: Photon detector eta

Figure 3: Corrected for vetrex photon eta

Figure 4: Away side jet detector eta

Figure 5: Corrected for vetrex away side jet eta

Figure 6:Photon pt

Figure 7: Away side jet pt

Figure 8: Pre-shower 1 energy

Figure 9: Pre-shower 2 energy

2009.02.06 Pre-shower energy distribution Run6 vs. Run8 geometry

Ilya Selyuzhenkov February 06, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • mc2006: gamma-jet+QCD jets [p6410EemcGammaFilter] events.
  • Partonic pt range 2-25 GeV.

  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV, jet pt > 7GeV
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered for pp2006 and pp2008 events
  • cos (phi_jet - phi_gamma) < -0.8
  • detector |eta_jet|< 0.8
  • |v_z| < 100

Figures

Each figure has:

  • All pre-shower conditions combined, No pre-shower cuts
  • Red circles show pp2006 data
  • Black triangles show pp2008 data
    Data scaled to match the integraled yield from pp2006 data
  • Green line shows MC sum: QCD + gamma-jet
    Monte-Carlo results for QCD and gamma-jet samples are first
    scaled to 3.164 pb^-1 according to Pythia luminosity,
    added together, and then an additional fudge factor of 1.24 applied.
    Fudge factor is defined as pp2006 to Monte-Carlo sum ratio
    for pt_jet>7GeV and pt_gamma>7 candidates

Observations

  • Pre-shower energy distributions from pp2008 data set
    are narrower than that for pp2006 data.
    This corresponds to smaller amount of material budget in y2008 STAR geometry.
  • Pre-shower energy distribution from Monte-Carlo with y2006 geometry
    closer follows the distribution from pp2008 data set, rather than that from pp2006 data.
    This indicates the lack of material budget in y2006 Monte-Carlo.

Note: There is a "pre-shower sector 10 problem" for pp2008 data,
which results in migration of small fraction of events with pre-shower>0 into
pre-shower=0 bin (first zero bins in Fig.1 and 2. below).
For pre-shower>0 case this only affects overall normalization of pp2008 data,
but not the shape of pre-shower energy distributions.
I'm running jet-finder+my software to get more statistics from pp2008 data set,
and after more QA will produce list of runs with "pre-shower sector 10 problem",
so to exclude them in the next iteration of my plots.

Figure 1: Pre-shower1 energy distribution

Figure 2: Pre-shower2 energy distribution

2009.02.09 pp2006, pp2008, amd mc2006 comparison

Ilya Selyuzhenkov February 06, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • mc2006: gamma-jet+QCD jets [p6410EemcGammaFilter] events.
  • Partonic pt range 2-25 GeV.

  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV, jet pt > 7GeV
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered for pp2006 and pp2008 events
  • cos (phi_jet - phi_gamma) < -0.8
  • detector |eta_jet|< 0.8
  • |v_z| < 100

Figures

Each figure has:

  • All pre-shower conditions combined, No pre-shower cuts
  • Red circles show pp2006 data
  • Black triangles show pp2008 data
    Data scaled to match the integraled yield from pp2006 data
  • Green line shows MC sum: QCD + gamma-jet
    Monte-Carlo results for QCD and gamma-jet samples are first
    scaled to 3.164 pb^-1 according to Pythia luminosity,
    added together, and then an additional fudge factor of 1.24 applied.
    Fudge factor is defined as pp2006 to Monte-Carlo sum ratio
    for pt_jet>7GeV and pt_gamma>7 candidates

Kinematics

Figure 1: vertex z

Figure 2: photon detector eta

Figure 3: jet detector eta

Figure 4: photon pt

Figure 5: jet pt

Figure 6: gamma-jet pt balance

Figure 7: Photon neutral energy fraction

Figure 8: Jet neutral energy fraction

Figure 9: cos(phi_gamma-phi_jet)

Photon candidate's 2x1, 2x2, and 3x3 tower cluser energy

Figure 10: 3x3 cluster energy

Figure 11: 2x1 cluster energy

Figure 12: 2x2 cluster energy

Number of charge tracks, Barrel and Endcap towers within r=0.7 for photon and gamma

Figure 13: Number of charged track associated with photon candidate

Figure 14: Number of Barrel towers associated with photon candidate

Figure 15: Number of Endcap towers associated with photon candidate

Jet energy composition

Figure 16: Jet energy part from Barrel towers

Figure 17: Jet energy part from charge tracks

2009.02.16 pt_jet>5GeV: pre-shower sorting with new normalization

Ilya Selyuzhenkov February 16, 2009

Data sets

  • pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1)
    Trigger: eemc-http-mb-L2gamma [id:137641]
  • mc2006: gamma-jet+QCD jets [p6410EemcGammaFilter] events.
  • Partonic pt range 2-25 GeV.

  • pp2008 - STAR 2008 pp data
    Trigger: etot-mb-l2 [id:7]

Cuts applied

  • Di-jet events
  • Require to reconstruct photon momentum (no gamma-jet isolation cuts)
  • Gamma pt > 7GeV, jet pt > 7GeV
  • L2gamma emulation in Monte-Carlo
  • L2gamma triggered for pp2006 and pp2008 events
  • cos (phi_jet - phi_gamma) < -0.8
  • detector |eta_jet|< 0.8
  • |v_z| < 100

Figures

Each figure has:

  • pp2008 data scaled to match the integraled yield from pp2006 data
  • mc2006 stand for MC sum: QCD + gamma-jet
    Monte-Carlo results for QCD and gamma-jet samples are first
    scaled to 3.164 pb^-1 according to Pythia luminosity,
    added together, and then an additional fudge factor of 1.24 applied.
    Fudge factor is defined as pp2006 to Monte-Carlo sum ratio
    for pt_jet>7GeV and pt_gamma>7 candidates

plots for pt_gamma>7GeV, pt_jet > 5GeV

  1. All pre-shower combined: 1D distributions
  2. All pre-shower combined: 2D correlations
  3. Pre-shower sorting 1D distributions

 

2009.02.19 Photon-jet analysis status update for Spin PWG

Photon-jet analysis status update for Spin PWG (February 19, 2009)

Slides: download pdf

Previous versions: v1, v2

Link for CIPANP abstract

 

 

CIPANP 2009 abstract on photon-jet measurement

CIPANP 2009 abstract on photon-jet study

Title:
"Photon-jet coincidence measurements
in polarized pp collisions at sqrt{s}=200GeV
with the STAR Endcap Calorimeter"

Abstract: download pdf

Previous versions: v1, v2, v3, v4

Conference link: CIPANP 2009

03 Mar

March 2009 posts

 

2009.03.02 Application of the neural network for the cut optimization (zero try)

Multilayer perceptron (feedforward neural networks)

Multilayer perceptron (MLP) is feedforward neural networks
trained with the standard backpropagation algorithm.
They are supervised networks so they require a desired response to be trained.
They learn how to transform input data into a desired response,
so they are widely used for pattern classification.
With one or two hidden layers, they can approximate virtually any input-output map.
They have been shown to approximate the performance of optimal statistical classifiers in difficult problems.

ROOT implementation for Multilayer perceptron

TMultiLayerPerceptron class in ROOT
mlpHiggs.C example

Application for cuts optimization in the gamma-jet analysis

Netwrok structure:
r3x3, (pt_gamma-pt_jet)/pt_gamma, nCharge, bBtow, eTow2x1: 10 hidden layers: one output later

Figure 1:

  • Upper left: Learning curve (error vs. number of training)
    Learing method is: Steepest descent with fixed step size (batch learning)
  • Upper right: Differences (how important are initial variableles for signal/background separation)
  • Lower left: Network structure (ling thinkness corresponds to relative weight value)
  • Lower right: Network output. Red - MC gamma-jets, blue QCD background, black pp2006 data

 

Figure 2: Input parameters vs. network output
Row: 1: MC QCD, 2: gamma-jet, 3 pp2006 data
Vertical axis: r3x3, (pt_gamma-pt_jet)/pt_gamma, nCharge, bBtow, eTow2x1
Horisontal axis: network output

Figure 3: Same as Fig. 2 on a linear scale

2009.03.09 Application of the LDA and MLP classifiers for the cut optimization

Cut optimization with Fisher's LDA and MLP (neural network) classifiers

ROOT implementation for LDA and MLP:

Application for cuts optimization in the gamma-jet analysis

LDA configuration: default

MLP configuration:

  • 2 hidden layers [N+1:N neural network configuration, N is number of input parameters]
  • Learning method: stochastic minimization (1000 learning cycles)

Input parameters (same for both LDA and MLP):

  1. Energy fraction in 3x3 cluster within a r=0.7 radius: r3x3
  2. Photon-jet pt balance: [pt_gamma-pt_jet]/pt_gamma
  3. Number of charge tracks within r=0.7 around gamma candidate
  4. Number of Endcap towers fired within r=0.7 around gamma candidate
  5. Number of Barrel towers fired within r=0.7 around gamma candidate

Figure 1: Signal efficiency and purity, background rejection (left),
and significance: Sig/sqrt[Sig+Bg] (right) vs. LDA (upper plots) and MLP (lower plots) classifier discriminants

Figure 2:

  1. Upper left: Rejection vs. efficiency
  2. Upper right: Purity vs. efficiency
  3. Lower left: Purity vs. Rejection
  4. Lower right: Significance vs. efficiency

 

Figure 3: Data to Monte-Carlo comparison for LDA (upper plots) and MLP (lower plots)
Good (within ~ 10%) match between data nad Monte-Carlo
a) up to 0.8 for LDA discriminant, and b) up to -0.7 for MLP.

Figure 4: Data to Monte-Carlo comparison for input parameters
from left to right
1) pt_gamma 2) pt_jet 3) r3x3 4) gamma-jet pt balance 5) N_ch[gamma] 6) N_eTow[gamma] 7) N_bTow[gamma]
Colour coding: black pp2006 data, red gamma-jet MC, green QCD MC, blue gamma-jet+QCD

Figure 5: Data to Monte-Carlo comparison:
correlations between input variables (in the same order as in Fig. 4)
and LDA classifier discriminant (horizontal axis).
1st raw: QCD MC; 2nd: gamma-jet MC; 3rd: pp2006 data; 4th: QCD+gamma-jet MC

Figure 6: Same as Fig. 6 for MLP discriminant

2009.03.26 Endcap photon-jet update at the STAR Collaboration meeting

Endcap photon-jet update at the STAR Collaboration meeting

04 Apr

April 2009 posts

2009.04.17 WSU nuclear seminar

The STAR spin program with longitudinally polarized proton beams

2009.04.21 Adding SMD info to the LDA

Cut optimization with Fisher's LDA classifier

ROOT implementation for LDA:

Application for cuts optimization in the gamma-jet analysis

LDA configuration: default

LDA input parameters:

  1. Energy fraction in 3x3 cluster within a r=0.7 radius: r3x3
  2. Photon-jet pt balance: [pt_gamma-pt_jet]/pt_gamma
  3. Number of charge tracks within r=0.7 around gamma candidate
  4. Number of Endcap towers fired within r=0.7 around gamma candidate
  5. Number of Barrel towers fired within r=0.7 around gamma candidate

Figure 1: LDA discriminant (no SMD involved in training)

Figure 2: LDA (no SMD): Efficiency, rejection, purity vs. discriminant

Figure 3: SMD energy in 25 central strips (LDA-dsicriminant>0, no pre-shower1 cut)

Figure 4: SMD energy in 25 central strips (LDA-dsicriminant>0, pre-shower1 < 10MeV)

Figure 5: Maximum residual (LDA-dsicriminant>0, no pre-shower1 cut)

Figure 6: Maximum residual (LDA-dsicriminant>0, pre-shower1 < 10MeV)

LDA+ SMD analysis

SMD info added:
a) energy in 5 central srtips
b) maximum sided residual

Figure 7:LDA with SMD: Efficiency, rejection, purity vs. LDA discriminant

Figure 8: LDA discriminant with SMD

Figure 9: Maximum residual (SMD LDA-dsicriminant>0, pre-shower1 < 10MeV)

LDA with and without SMD comparison

Figure 10:LDA (no SMD): Efficiency, rejection, purity plots

Figure 11: LDA with SMD: Efficiency, rejection, purity plots

2009.04.28 LDA plus SMD analysis with pre-shower sorting

Cut optimization with Fisher's LDA classifier

ROOT implementation for LDA:

Application for cuts optimization in the gamma-jet analysis

LDA configuration: default

LDA input parameters (includes SMD inromation of the distance from max sided residual plot):

  1. Energy fraction in 3x3 cluster within a r=0.7 radius: r3x3
  2. Photon-jet pt balance: [pt_gamma-pt_jet]/pt_gamma
  3. Number of charge tracks within r=0.7 around gamma candidate
  4. Number of Endcap towers fired within r=0.7 around gamma candidate
  5. Number of Barrel towers fired within r=0.7 around gamma candidate
  6. Distance to 80% cut line (see this link for more details)

The number of strips in SMD u or v planes is required to be greater than 3

Figure 1: SMD energy in 25 central strips sorted by pre-shower energy

  1. Upper left: pre1=0, pre2=0
  2. Upper right: pre1=0, pre2>0
  3. Lower left: 0<4MeV
  4. Lower right: 4<10MeV

Right plot for each pre-shower condition shows the ratio of pp2006 data to sum of the Monte-Carlo samples
Colour coding:
black pp2006 data, red gamma-jet MC, green QCD MC, blue gamma-jet+QCD
(combined plot for all pre-shoer bins can be found here)

 

Figure 2: SMD energy in 5 central strips sorted by pre-shower energy
(combined plot can be found here)

Figure 3: Maximum residual sorted by pre-shower energy
(combined plot can be found here)

Figure 4: LDA discriminant. Note: LDA algo trained for each pre-shower condition independently

Figure 5: LDA: Efficiency, rejection, purity vs. discriminant, sorted by pre-shower energy

Figure 6: LDA: Efficiency, rejection, purity plots sorted by pre-shower energy
For each pre-shower condition each plot has 4 figures:

  1. u-left: rejection vs. efficiency
  2. u-right: purity vs. efficiency
  3. l-left: purity vs. rejection
  4. l-right: significance (signal/sqrt{signal+background}) vs. efficiency


 

05 May

May 2009 posts

 

2009.05.03 LDA: varying pt and eta cut

Cut optimization with Fisher's LDA classifier

ROOT implementation for LDA:

Application for cuts optimization in the gamma-jet analysis

LDA configuration: default

LDA input parameters Set0:

  1. Set0:
    • Energy fraction in 3x3 cluster within a r=0.7 radius:
      E_3x3/E_0.7
    • Photon-jet pt balance:
      [pt_gamma-pt_jet]/pt_gamma
    • Number of charge tracks within r=0.7 around gamma candidate:
      Ncharge
    • Number of Endcap towersL fired within r=0.7 around gamma candidate:
      NtowBarrel
    • Number of Barrel towers fired within r=0.7 around gamma candidate
      NtowEndcap
  2. Set1:
  3. Set2:
    • All from Set1
    • Energy fraction in E_2x1 and E_2x2 witin E_3x3:
      E_2x1/E_2x2 and E_2x2/E_3x3
  4. Set3:
    • All from Set2
    • Energy in post-shower layer under 3x3 tower patch:
      E_post^3x3

The number of strips in SMD u or v planes is required to be greater than 3

Pre-shower sorting (energy in tiles under 3x3 tower patch):

  1. pre1=0, pre2=0
  2. pre1=0, pre2>0
  3. 0 < pre1 < 0.004
  4. 0.004 < pre1 < 0.01
  5. pre1 < 0.01
  6. pre1 >= 0.01

Photon pt and rapidity cuts:

  1. pt>7GeV
  2. pt>8GeV
  3. pt>9GeV
  4. pt>10GeV
  5. detector eta <1.4 (pt>7GeV)
  6. detector eta > 1.4 (pt>7GeV)

Figure 0: photon pt distribution for pre-shower1<0.01
Colour coding:
black pp2006 data, red gamma-jet MC, green QCD MC, blue gamma-jet+QCD

LDA Set0

Figure 1: LDA discriminant with Set0: Data to Monte-Carlo comparison (pt>7GeV cut)

Right plot for each pre-shower condition shows the ratio of pp2006 data to sum of the Monte-Carlo samples
Colour coding:
black pp2006 data, red gamma-jet MC, green QCD MC, blue gamma-jet+QCD


Figure 2: efficiency, purity, rejection vs. LDA discriminant (pt>7GeV cut)


Figure 3: rejection vs. efficiency

Figure 4: purity vs. efficiency

Figure 5: purity vs. rejection

LDA Set1

Figure 6: LDA discriminant with Set1: Data to Monte-Carlo comparison


Figure 7: rejection vs. efficiency

Figure 8: purity vs. efficiency

Figure 9: purity vs. rejection (click link to see the figure)

LDA Set2

Figure 10: rejection vs. efficiency (click link to see the figure)

Figure 11: purity vs. efficiency

Figure 12: purity vs. rejection (click link to see the figure)

LDA Set3

Figure 13: rejection vs. efficiency (click link to see the figure)

Figure 14: purity vs. efficiency

Figure 15: purity vs. rejection (click link to see the figure)

2009.05.04 LDA: More SMD info, 3x3 tower energy, correlation matrix

Cut optimization with Fisher's LDA classifier

ROOT implementation for LDA:

Application for cuts optimization in the gamma-jet analysis

LDA configuration: default

LDA input parameters Set0:

  1. Set4 (link for results with LDA Set0-Set3):
    • Energy fraction in 3x3 cluster within a r=0.7 radius:
      E_3x3/E_0.7
    • Photon-jet pt balance:
      [pt_gamma-pt_jet]/pt_gamma
    • Number of charge tracks within r=0.7 around gamma candidate:
      Ncharge
    • Number of Endcap towersL fired within r=0.7 around gamma candidate:
      NtowBarrel
    • Number of Barrel towers fired within r=0.7 around gamma candidate
      NtowEndcap
    • Shower shape analysis: distance to 80% cut line:
      distance to cut line
    • Energy fraction in E_2x1 and E_2x2 witin E_3x3:
      E_2x1/E_2x2 and E_2x2/E_3x3
    • Energy in post-shower layer under 3x3 tower patch:
      E_post^3x3
    • Tower energy in 3x3 patch:
      E_tow^3x3
    • SMD-u energy in 25 central strips:
      E_smd-u^25
    • SMD-v energy in 25 central strips:
      E_smd-v^25
    • SMD-v peak energy (in 5 central strips):
      E_peak

The number of strips in SMD u or v planes is required to be greater than 3

Pre-shower sorting (energy in tiles under 3x3 tower patch):

  1. pre1=0, pre2=0
  2. pre1=0, pre2>0
  3. 0 < pre1 < 0.004
  4. 0.004 < pre1 < 0.01
  5. pre1 < 0.01
  6. pre1 >= 0.01

Integrated yields per pre-shower bin:

sample total integral pre1=0,pre2=0 pre1=0, pre2>0 0 < pre1 < 0.004 0.004 < pre1 < 0.01 pre1 < 0.01 pre1 >= 0.01
photon-jet 2.5640e+03 3.5034e+02 5.2041e+02 5.6741e+02 5.2619e+02 1.9644e+03 5.9994e+02
QCD 5.6345e+04 1.3515e+03 4.3010e+03 1.2289e+04 1.5759e+04 3.3701e+04 2.2644e+04
pp2006 6.2811e+04 6.8000e+02 2.4310e+03 1.2195e+04 1.6766e+04 3.2072e+04 3.0739e+04

Photon pt and rapidity cuts:

  1. pt>7GeV
  2. pt>8GeV
  3. pt>9GeV
  4. pt>10GeV
  5. detector eta <1.4 (pt>7GeV)
  6. detector eta > 1.4 (pt>7GeV)

LDA Set4

Figure 1: LDA discriminant with Set0: Data to Monte-Carlo comparison (pt>7GeV cut)

Right plot for each pre-shower condition shows the ratio of pp2006 data to sum of the Monte-Carlo samples
Colour coding:
black pp2006 data, red gamma-jet MC, green QCD MC, blue gamma-jet+QCD


Figure 2: rejection vs. efficiency

Figure 3: purity vs. efficiency

Figure 4: purity vs. rejection

Figure 5: Correlation matrix (pt>7GeV cut)
pre1=0, pre2=0

pre1=0, pre2>0

0 < pre1 < 0.004

0.004 < pre1 < 0.01

pre1 < 0.01

pre1 >= 0.01

2009.05.06 Applying cuts on LDA: request minimum purity or efficiency

Cut optimization with Fisher's LDA classifier

For this post LDA input parameters Set4 has been used

LDA for various pre-shower bins is trained independetly,
and later results with pre-shower1<0.01 are combined.

There are a set of plots for various photon pt cuts (pt> 7, 8, 9 10 GeV)
and with different selection of cutoff for LDA
(either based on purity or efficiency).
Number in brackets shows the total yield for the sample.

Link to all plots (16 total) as a single pdf file

pt > 7GeV

Figure 1: pt > 7GeV, efficiency@70

Figure 2: pt > 7GeV, purity@35

 

Figure 3: pt > 7GeV, purity@40

 

Figure 4: pt > 7GeV, purity@25 (Note: very similar to results with efficiency@70)

 

pt > 9GeV

Figure 5: pt > 9GeV, efficiency@70

 

Figure 6: pt > 9GeV, purity@35

 

pt > 10GeV

Figure 7: pt > 10GeV, efficiency@70

 

Figure 8: pt > 10GeV, purity@40

 

2009.05.07 Photon-jets analysis with the Endcap Calorimeter

Photon-jets with the Endcap Calorimeter

(analysis status update for Spin PWG)

Slides in pdf format:

 

2009.05.12 Variable distributions after LDA at 70% efficiency

Cut optimization with Fisher's LDA classifier

For this post LDA results with Set1 and Set2 has been used
Note, that LDA for various pre-shower bins is trained independetly

pdf-links with results for pre1=0 and pre2=0 (pre-shower bin 1):

Figures below are for 0.004<pre-shower1<0.01 (pre-shower bin 4).

Photon pt cut: pt> 7, pre-shower bin: 0.004 < pre1 < 0.01
LDA cut with efficiency @ 70%

Set1 vs. Set2

What is added in Set2 compared to Set1:
smaller cluster size information (r2x1, r2x2), post-shower energy

Figure 1: r2x1
before LDA cut

LDA cut for Set1

LDA cut for Set2

Figure 2: r2x2
before LDA cut

LDA cut for Set1

LDA cut for Set2

Figure 3: r3x3
before LDA cut

LDA cut for Set1

LDA cut for Set2

Figure 4: Residual distance
before LDA cut

LDA cut for Set1

LDA cut for Set2

Other variables with LDA Set2 cut

Note: Only plos for LDA cut @70 efficiency for Set2 are shown

Figure : number of charge particles around photon

 

Figure 5: number of EEMC tower around photon

 

Figure 6: number of BEMC tower around photon

 

Figure 7: photon-jet pt balance

 

Figure 8: SMD energy in 5 centrapl strips

 

Figure 9: SMD energy in 25 central strips: u and v plane separately (plot for V plane)

 

Figure 10: 2x1 cluster energy

 

Figure 11: 2x2 cluster energy

 

Figure 12: 3x3 cluster energy

 

Figure 13: tower energy in r=0.7 radius

 

Figure 14: 3x3 pre-shower1 energy

 

Figure 15: 3x3 pre-shower2 energy

 

Figure 16: 3x3 post-shower energy

 

Figure 17: photon pt

 

Figure 18: jet pt

 

Figure 19: z vertex

2009.05.31 CIPANP 2009 photon-jet presentation

CIPANP 2009 presentation on photon-jet study

Title:
"Photon-jet coincidence measurements
in polarized pp collisions at sqrt{s}=200GeV
with the STAR Endcap Calorimeter"

06 Jun

June 2009 posts

 

2009.06.22 CIPANP 2009 photon-jet proceedings

CIPANP 2009 proceedings on photon-jet study

Title:
"Photon-jet coincidence measurements
in polarized pp collisions at sqrt{s}=200 GeV
with the STAR Endcap Calorimeter"

07 Jul

July 2009 posts

 

2009.07.21 EEMC tower response in Monte-Carlo

Data set and cuts:

  1. gamma-jet filtered Monte-Carlo
  2. Di-jet events from the jet finder (jets threshold: 3.5 GeV)
  3. parton pt bin 3-4 GeV (see pt_gamma distributions for various parton pt bins)
  4. Thrown photon pseudo-rapidity: eta in [1-2] range
  5. Requires to reconstruct photon candidate in the EEMC

Figure 1: Average ratio: pt_true / (pt_reco/1.3) vs. pt_reco (GeV/c)

  • Introduce 1.3 factor here to remove the effect of the fudge factor in slow simulator
  • Since a limited partonic pt range (3-4 GeV) is used for this study,
    there is an "artificial" increase of the plotted ratio in pt_gamma > 6 GeV range
  • Fig. 1 reflects similar features (over a limited pt range) as those found by Hal
    in his single photon study (see slide 6 of SimulationStudies.ppt presentation)

 

Figure 2:
Average momentum difference: pt_true - (pt_reco/1.3) vs. pt_reco (GeV/c)

  • Fig. 2 shows that on average in GEANT Monte-Carlo we miss ~1GeV independent on the photon pt.
    EEMC detector response can be still linear even if the ratio in Fig. 1 is not flat.
  • Usage of fixed 1.3 (or others, like 1.25) fudge factors are not justified.
  • It seems that using pt-dependent fudge factor (like it is done in this Jason's study)
    is also unjustified, since the same effects (flat ratio of pt_reco/pt_true ~ 1)
    can be reached by subtracting 1 GeV from the cluster energy (See Fig. 3).

 

Figure 3: Average ratio: (pt_true -1.06) (pt_reco/1.3) vs. pt_reco (GeV/c)
Similar to Fig. 1, but with the true photon pt reduced by 1.06 GeV
Resulting true/reco pt ratio is flat in 4-6 GeV range.

Before further pursuing our efforts in tuning the tower energy response in the Monte-Carlo,
needs to address the observed energy loss difference in the fisrt layer of the BEMC/EEMC detector.
See Jason's blog post from 2009.07.16 for more details:
Comparison muon energy deposit in the 1st BEMC/EEMC layers

08 Aug

August 2009 posts

 

2009.08.24 Test of corrected EEMC geometry

Test of corrected EEMC geometry (bug 1618)

Monte-Carlo setup:

  • One particle per event (photons, electrons, and pions)
  • Full STAR 2006 geometry.
    In Kumac file: detp geom y2006g; gexec $STAR_LIB/geometry.so
  • Flat in eta (1.08-2.0), phi (0,2pi), and pt (3-30 GeV)
  • Using A2Emaker to get reconstructed Tower/SMD energy (no EEMC SlowSimulator in chain)
    what assumes fixed sampling fraction of 0.05 (5%)

Some definitions:

  • Et correction factor : average p_T^thrown / E_T^{reco}.
    E_T^{reco} is the total energy in the Endcap Calorimeter (from A2Emaker)
  • Sampling fraction: average 0.05 * Energy^{reco} / Energy^thrown.
  • SMD energy: average energy in all strips fired (u-plane used for this post)
  • Number of SMD strips fired: average total number of strips fired (u-plane used for this post)

Notations used in the plots:

  • Left plots: no cAir fix
  • Right plots: cAir-fixed
  • Photons: black
  • Electrons: red
  • Pions: green

Et correction

Note: compare "Left" plots with Brians old results

Figure 1a: Et correction factor vs. pt thrown

Figure 1b: Et correction factor vs. eta thrown

Figure 1c: Et correction factor vs. phi thrown

Sampling fraction

Note: compare "Right" plots with Jason results with EEMC only geometry

Figure 2a: Sampling fraction vs. pt thrown

Figure 2b: Sampling fraction vs. energy thrown

Figure 2c: Sampling fraction vs. eta thrown

Figure 2d: Sampling fraction vs. phi thrown

SMD energy

Figure 3a: SMD energy vs. energy thrown

Figure 3b: SMD energy vs. eta thrown

Number of SMD strips fired

Figure 4a: Number of SMD strips fired vs. energy thrown

Figure 4b: Number of SMD strips fired vs. eta thrown

2009.08.25 Test of corrected EEMC geometry: shower shapes

Test of corrected EEMC geometry (bug 1618)

Monte-Carlo setup is desribed here

  • One particle per event (photons, electrons, and pions)
  • Full STAR 2006 geometry.
    In Kumac file: detp geom y2006g; gexec $STAR_LIB/geometry.so
  • Flat in eta (1.08-2.0), phi (0,2pi), and pt (3-30 GeV)
  • Using A2Emaker to get reconstructed Tower/SMD energy (no EEMC SlowSimulator in chain)
    what assumes fixed sampling fraction of 0.05 (5%)
  • Vertex z=0
  • ~50K/per particle type
  • Non-zero energy: 3 sigma above pedestal

Figure 1:Single photon shower shape before (red) and after (black) EEMC cAir bug fixed
pt=7-8GeV, eta=1.2-1.4 (left), eta=1.6-1.8 (right)

Figure 2: Single photon shower shape vs. data
Monte-Carlo: pt=7-10GeV, eta=1.6-1.8
data: no pre-shower1,2; pt_photon>7, pt_jet>5. no eta cuts.
(see Fig. 1 from here for other pre-shower conditions)

2009.08.27 fixed EEMC geometry: pre-shower sorted shower shapes & eta-meson comparison

Test of corrected EEMC geometry: shower shapes (bug 1618)

Monte-Carlo setup is desribed here

  • One particle per event (photons, electrons, and pions)
  • Full STAR 2006 geometry.
    In Kumac file: detp geom y2006g; gexec $STAR_LIB/geometry.so
  • Flat in eta (1.08-2.0), phi (0,2pi), and pt (3-30 GeV)
  • Using A2Emaker to get reconstructed Tower/SMD energy (no EEMC SlowSimulator in chain)
    what assumes fixed sampling fraction of 0.05 (5%)
  • Vertex z=0
  • ~50K/per particle type
  • Non-zero energy: 3 sigma above pedestal

Color coding:

  • Black - photon (single particle/event MC)
  • Red - electron (single particle/event MC)
  • Green - neutral pion (single particle/event MC)
  • Blue - photons from eta-meson decay (real data)

Single particle shower shape before (left) and after (right) EEMC cAir bug fixed
Single particle kinematic cuts: pt=7-8GeV, eta=1.2-1.4
Eta-meson shower shapes (blue) taken from Fig. 1 from here of this post
All shapes are normalized to 1 at peak (central strip).

Figure 1: Pre-shower bin 0: E_pre1=0; E_pre2=0

Figure 2: Pre-shower bin 1: E_pre1=0; E_pre2>0

Figure 3: Pre-shower bin 2: E_pre1>0; E_pre1<0.004

Figure 4: Pre-shower bin 3: E_pre1>0.004; E_pre1<0.01

Shower shape ratios

Results only for corrected EEMC geometry
All shapes are divided by MC single-photon shower shape.

Figure 5a: Pre-shower bin 0: E_pre1=0; E_pre2=0

Figure 5b: Pre-shower bin 1: E_pre1=0; E_pre2>0

Figure 5c: Pre-shower bin 2: E_pre1>0; E_pre1<0.004

Figure 5d: Pre-shower bin 3: E_pre1>0.004; E_pre1<0.01

Figure 6: Single photon to eta-meson shape ratios only (with error bars):
Pre-shower bins 0 (upper-left),1 (upper-right),2 (lower-left), and 3 (lower-right)

Extracting gamma-jet cross section at forward rapidity from pp@200GeV collisions

Analysis overview

  1. Data samples, event selection, luminosity determination
  2. Isolating photon-jet events
    • Transverse shower shape analysis
    • Isolation cuts
    • Cut optimization
  3. Trigger effects study
  4. Data to Monte-Carlo comparison/normalization and raw yields
  5. Acceptance/efficiency corrections
  6. Corrected yields
  7. Background subtraction
  8. Systematic uncertainties
  9. Comparison with theory

Data samples, event selection, luminosity determination

Real data, and signal/background Monte-Carlo samples:

  • pp@200GeV collisions, STAR produnctionLong.
    Trigger: eemc-http-mb-L2gamma [id:137641] (L ~ 3.164 pb^1)

  • Pythia prompt photon (signal) Monte-Carlo sample.
    Filtered Prompt Photon p6410EemcGammaFilter.
    Partonic pt range 2-25 GeV.

  • Pythia 2->2 hard QCD processes (background) Monte-Carlo sample.
    Filtered QCD p6410EemcGammaFilter.
    Partonic pt range 2-25 GeV.

Isolating photon-jet events

  1. Shower shape analysis
  2. Isolation cuts
  3. Cut optimization with LDA.
    Input variables (list can be expanded):
    • Energy fraction in 3x3 cluster within a r=0.7 radius, E_3x3/E_0.7
    • Photon-jet pt balance, [pt_gamma-pt_jet]/pt_gamma
    • Number of charge tracks within r=0.7 around gamma candidate
    • Number of Endcap towers fired within r=0.7 around gamma candidate
    • Number of Barrel towers fired within r=0.7 around gamma candidate
    • Shower shape analysis: distance to 80% cut line
    • Energy fraction in E_2x1 and E_2x2 witin E_3x3
    • Energy in post-shower layer under 3x3 tower patch
    • Tower energy in 3x3 patch
    • SMD-u/v energy in 25 central strips
    • SMD-u/v peak energy (in 5 central strips)

Trigger effects study

No studies yet

  • Trigger effects vs pt
  • Trigger effects vs eta
  • What else?

Data to Monte-Carlo comparison/normalization and raw yields

  • Overall data to MC normalization based on vertex z distribution
  • Data to MC comparison of raw yield in various detector subsystems
  • Uncorrected yields optimized with different efficiency/purity

Acceptance/efficiency corrections

No studies yet

  • What needs to be studied for acceptance/efficiency effects?
  • Converting reconstructed photon (jet) energy/momentum to the true one
  • Reconstruction efficiency vs. rapidity, pt, etc

Corrected yields

No studies yet

  • Produce acceptance/efficiency corrected yields

Background subtraction

No studies yet

  • Statistical background subtraction based on Pythia+GEANT Monte-Carlo
  • Estimate systematic uncertainties due to background subtraction

Systematic uncertainties

No studies yet

  • Calorimeter energy resolution
  • Trigger bias
  • Other effects

Comparison with theory

No comparison yet

  • Request for pQCD calculations at forward rapidity

09 Sep

September 2009 posts

2009.09.04 Test of corrected EEMC geometry: SVT, slow-simulator on/off, pre-shower migration

Test of corrected EEMC geometry: shower shapes (bug 1618)

Monte-Carlo setup:

  • One particle per event (photons, electrons, pions, and eta-meson)
  • Full STAR 2006 geometry (with/without SVT)
    In Kumac file: detp geom y2006g; gexec $STAR_LIB/geometry.so (remove SVT with SVTT_OFF option)
  • Throw particles flat in eta (1.08, 2.0), phi (0, 2pi), and pt (6-10 GeV)
  • Using A2Emaker to get reconstructed Tower/SMD energy
    (with/without EEMC SlowSimulator in chain)
  • Vertex z=0
  • ~50K/per particle type
  • Non-zero energy: 3 sigma above pedestal

Color coding:

  • Photon (single particle MC)
  • Electron (single particle MC)
  • Neutral pion (single particle MC)
  • Eta-meson (single particle MC)
  • Eta-meson [pp2006 data] (single photons from eta-meson decay)

Pre-shower bins:

  1. Ep1 = 0, Ep2 = 0 (no energy in both EEMC pre-shower layers)
  2. Ep1 = 0, Ep2 > 0
  3. 0 < Ep1 < 4 MeV
  4. 4 < Ep1 < 10 MeV
  5. Ep1 > 10 MeV
  6. All pre-shower bins combined

Ep1/Ep2 is the energy deposited in the 1st/2nd EEMC pre-shower layer.
For a single particle MC it is a sum over
all pre-shower tiles in the EEMC with energy of 3 sigma above pedestal.
For eta-meson from pp2006 data the sum is over 3x3 tower patch

Shower shapes

Single particle kinematic cuts: pt=7-8GeV, eta=1.2-1.4
Eta-meson shower shapes (blue) taken from Fig. 1 from here of this post
All shapes are normalized to 1 at peak (central strip)

Figure 1: Shower shape sorted by pre-shower conditions.
cAir-Fixed EEMC geometry (NO slow simulator, WITH SVT)
Ratio plot

Figure 2: Shower shape sorted by pre-shower conditions.
cAir-Fixed EEMC geometry (NO slow simulator, NO SVT)
Ratio plot

Figure 3: Shower shape sorted by pre-shower conditions.
cAir-Fixed EEMC geometry (WITH slow simulator, WITH SVT)
Ratio plot

Figure 4: Shower shape sorted by pre-shower conditions.
Old cAir-bug EEMC geometry (NO slow simulator, WITH SVT)
Click here to see the plot

Pre-shower migration with/without SVT

Starting with a fixed (50K events) for each type of particle.
Change in number of counts for a given pre-shower bin
with different detector configuration shows pre-shower migration

Figure 5: Pre-shower migration.
cAir-Fixed EEMC geometry (WITH SVT)

Figure 6: Pre-shower migration.
cAir-Fixed EEMC geometry (WITHOUT SVT)

Sampling fraction with/without Slow-simulator

Figure 7: Sampling fraction (0.05 E_reco / E_thrown).
cAir-Fixed EEMC geometry (WITHOUT Slow-simulator)

Figure 8: Sampling fraction (0.05 E_reco / E_thrown).
cAir-Fixed EEMC geometry (WITH Slow-simulator)
Slow simulator introduce some non-linearity in the sampling fraction

Figure 9: Sampling fraction (0.05 E_reco / E_thrown).
cAir-Fixed EEMC geometry (WITHOUT SVT, WITHOUT Slow-simulator)
Click here to see the plot

Figure 10: Sampling fraction (0.05 E_reco / E_thrown).
Old cAir-bug EEMC geometry (NO slow simulator, WITH SVT)
Click here to see the plot

2009.09.11 Test of corrected EEMC geometry: LOW_EM cuts

Test of corrected EEMC geometry: SVT and LOW_EM cuts

Monte-Carlo setup:

  • One particle per event (only photons in this post)
  • Full STAR 2006 geometry (with/without SVT, LOW_EM cuts)
    In Kumac file: detp geom y2006g; gexec $STAR_LIB/geometry.so (vary SVTT_OFF, LOW_EM)
    LOW_EM cut definition is given at the end of this page
  • Throw particles flat in eta (1.2, 1.9), phi (0, 2pi), and pt (6-10 GeV)
  • Using A2Emaker to get reconstructed Tower/SMD energy
    (this post: no EEMC SlowSimulator)
  • Vertex z=0
  • ~50K/per iteration
  • Non-zero energy: 3 sigma above pedestal

Color coding:

  • SVT, LOW_EM marked in legend as LowEM (single photon MC)
  • STV, no-LOW_EM marked in legend as default (single photon MC)
  • no-SVT, no-LOW_EM marked in legend as no-SVT (single photon MC)
  • photon-jet candidates [pp2006] (used data points from this post)
  • photons from eta-meson [pp2006]

Pre-shower bins:

  1. Ep1 = Ep2 = 0 (no energy in both EEMC pre-shower layers)
  2. Ep1 = 0, Ep2 > 0
  3. 0 < Ep1 < 4 MeV
  4. 4 < Ep1 < 10 MeV
  5. Ep1 > 10 MeV
  6. All pre-shower bins combined

Note: Ep1/Ep2 is the energy deposited in the 1st/2nd EEMC pre-shower layer.
For a single photon MC it is a sum over
all pre-shower tiles in the EEMC with energy of 3 sigma above pedestal.
For eta-meson/gamma-jet candidates from pp2006 data the sum is over 3x3 tower patch

Shower shapes

Single particle kinematic cuts: pt=7-8GeV, eta=1.2-1.4
Eta-meson shower shapes (blue) taken from Fig. 1 from here of this post
All shapes are normalized to 1 at peak (central strip)

Figure 1: Shower shape sorted by pre-shower conditions.

Figure 2: Shower shape ratio. All shapes in Fig. 1 are divided by single photon shape
for "SVT+LOW_EM" configuration (black circles in Fig. 1)

Sampling fraction

Figure 3: Sampling fraction (0.05 * E_reco/ E_thrown)

Pre/post-shower energy and migration

Figure 4: Pre-shower1 energy (all tiles)

Figure 5: Pre-shower2 energy (all tiles)

Figure 6: Post-shower energy (all tiles)

Figure 7: Pre-shower bin photon migration

Tower energy profile

Figure 8a: Energy ratio in 2x1 to 3x3 cluster
For the first 4 pre-shower bins total yield in MC is normalized to that of the data
Blue circles indicate photon-jet candidates [pp2006] (points from this post)
Same data on a linear scale

Figure 8b: Energy ratio in 2x1 to 3x3 cluster: 7 < pt < 8 and 1.2 < eta < 1.4

 

Figure 8c: Energy ratio in 2x1 to 3x3 cluster: 7 < pt < 8 and 1.6 < eta < 1.8

Figure 9: Average energy ratio in 2x1 to 3x3 cluster vs. thrown energy

Figure 10: Average energy ratio in 2x1 to 3x3 cluster vs. thrown energy

LOW_EM cut definition

LOW_EM option for the STAR geometry (Low cuts on Electro-Magnetic processes)
is equivalent to the following set of GEANT cuts:

  • CUTGAM=0.00001
  • CUTELE=0.00001
  • BCUTE =0.00001
  • BCUTM =0.00001
  • DCUTE =0.00001
  • DCUTM =0.00001

All these values are for kinetic energy in GeV.

 

Cut meaning and GEANT default values:

  • CUTGAM threshold for gamma transport (0.001);
  • CUTELE threshold for electron and positron transport (0.001);
  • BCUTE threshold for photons produced by electron bremsstrahlung (-1,);
  • BCUTM threshold for photons produced by muon bremsstrahlung (-1);
  • DCUTE threshold for electrons produced by electron delta-rays (-1);
  • DCUTM threshold for electrons produced by muon or hadron delta-rays (-1);

Some details can be found at this link and in the GEANT manual

 

10 Oct

October 2009 posts

2009.10.02 Jason vs. CVS EEMC geometry: sampling fraction and shower shapes

Tests with Jason geometry file (ecalgeo.g23)

Monte-Carlo setup:

  • One photon per event
  • EEMC only geometry with LOW_EM option
  • Throw particles flat in eta (1.08, 2.0), phi (0, 2pi), and pt (6-10 GeV)
  • Using A2Emaker to get reconstructed Tower/SMD energy
    (no EEMC SlowSimulator in chain)
  • Vertex z=0
  • ~50K/per particle type
  • Non-zero energy: 3 sigma above pedestal

Color coding:

  • Photon with Jason geometry (single particle MC)
  • Photon with CVS (cAir fix) geometry (single particle MC)
  • Eta-meson [pp2006 data] (single photons from eta-meson decay)

Sampling fraction

Figure 1: Sampling fraction vs. thrown energy (upper plot)
and vs. azimuthal angle (lower left) and rapidity (lower right)

Shower shapes

Single particle kinematic cuts: pt=7-8GeV, eta=1.2-1.4
Eta-meson shower shapes (blue) taken from Fig. 1 from here of this post
All shapes are normalized to 1 at peak (central strip)

Figure 2: Shower shapes

Shower shapes sorted by pre-shower energy

Pre-shower bins:

  1. Ep1 = 0, Ep2 = 0 (no energy in both EEMC pre-shower layers)
  2. Ep1 = 0, Ep2 > 0
  3. 0 < Ep1 < 4 MeV
  4. 4 < Ep1 < 10 MeV
  5. Ep1 > 10 MeV
  6. All pre-shower bins combined

Ep1/Ep2 is the energy deposited in the 1st/2nd EEMC pre-shower layer.
For a single particle MC it is a sum over
all pre-shower tiles in the EEMC with energy of 3 sigma above pedestal.
For eta-meson from pp2006 data the sum is over 3x3 tower patch

Figure 3: Shower shapes (left) and their ratio (right)

Figure 4: Shower shape ratios

2009.10.05 Fix to the Jason geometry file

Why volume numbers has changed in Jason geometry file?

The number of nested volumes (nv),
is the total number of parent volumes for the sensitive volume
(sensitive volume is indicated by the HITS in the tree structure below).

For the Jason and CVS files this nv number seems to be the same
(see block tree structures below).
Then why volume ids id in g2t tables has changed?

The answer I found (which seems trivial to me know)
is that in the original (CVS) file ECAL
block has been instantiated (positioned) twice.
The second appearance is the prototype (East) version of the Endcap
(Original ecalgeo.g from CVS)

        if (emcg_OnOff==1 | emcg_OnOff==3) then
             Position ECAL in CAVE z=+center
        endif
        if (emcg_OnOff==2 | emcg_OnOff==3) then
             Position ECAL in CAVE z=-center ThetaZ=180
        endif

In Jason version the second appearance has been removed
(what seems natural and it should not have any effect)
(ecalgeo.g Jason edits, g23):

        IF (emcg_OnOff>0) THEN
           Create ECAL

              .....

        IF (emcg_OnOff==2 ) THEN
           Prin1
             ('East Endcap has been removed from the geometry' )
        ENDIF               EndIF! emcg_OnOff

Unfortunately, this affects the way GEANT counts nested volumes

 

(effectively the total number was reduced by 1, from 8 to 7)

 

and this is the reason why the volume numbering scheme

 

in g2t tables has been affected.

 

I propose to put back these East Endcap line back,

 

since in this case it  will not require any additional

 

changes to the EEMC decoder and g2t tables.

 

 

Block tree of the geometry file

blue - added volumes in Jason file
red - G10 volume removed in Jason file
HITS - sensitive volumes

 ---- Jason file ----

ECAL
 EAGA
  |EMSS
  |  -EFLP
  |  |ECVO
  |  |  |EMOD
  |  |  |  |ESEC
  |  |  |  |  |ERAD
  |  |  |  |  | -ELED
  |  |  |  |  |EMGT
  |  |  |  |  |  |EPER
  |  |  |  |  |  |  |ETAR
  |  |  |  |  |  |  |  -EALP
  |  |  |  |  |  |  |  -ESCI -> HITS
  |  |ESHM
  |  |  |ESPL
  |  |  |  |EXSG
  |  |  |  |  -EXPS
  |  |  |  |  -EHMS -> HITS
  |  |  |  |  -EBLS
  |  |  |  |  -EFLS
  |  |  |ERSM
  |  -ESSP
  |  -ERCM
  |  -EPSB
  |ECGH
  |  -ECHC


---- CVS file ----
ECAL
 EAGA
  |EMSS
  |  -EFLP
  |  |ECVO
  |  |  |EMOD
  |  |  |  |ESEC
  |  |  |  |  |ERAD
  |  |  |  |  | -ELED
  |  |  |  |  |EMGT
  |  |  |  |  |  |EPER
  |  |  |  |  |  |  |ETAR
  |  |  |  |  |  |  |  -EALP
  |  |  |  |  |  |  |  -ESCI -> HITS
  |  |ESHM
  |  |  |ESPL
  |  |  |  |EXSG
  |  |  |  |  -EHMS -> HITS
  |  |  |  -EXGT
  |  |  -ERSM
  |  -ESSP
  |  -ERCM
  |  -EPSB
  |ECGH
  |  -ECHC

 

 

Block definitions

Jason geometry file 

Create ECAL

Block ECAL is one EMC EndCap wheel
  Create and Position EAGA AlphaZ=halfi
EndBlock

Block EAGA IS HALF OF WHEEL AIR VOLUME FORTHE ENDCAP MODULE
  Create AND Position EMSS konly='MANY'
  Create AND Position ECGH alphaz=90 kOnly='ONLY'
EndBlock

Block EMSS is the steel support of the endcap module
  Create AND Position EFLP z=zslice-center+zwidth/2
  Create AND Position ECVO z=zslice-center+zwidth/2
  Create AND Position ESHM z=zslice-center+zwidth/2 kOnly='MANY'
  Create AND Position ECVO z=zslice-center+zwidth/2
  Create AND Position ESSP z=zslice-center+zwidth/2
  Create ERCM
  Create EPSB
EndBlock

Block ECVO is one of endcap volume with megatiles and radiators
  Create AND Position EMOD alphaz=d3 ncopy=i_sector
EndBlock

Block ESHM is the shower maxsection
  Create and Position ESPL z=currentk Only='MANY'
  Create ERSM
EndBlock

Block ECGH is air gap between endcap half wheels
  Create ECHC
EndBlock

Block ECHC is steel endcap half cover
EndBlock

Block ESSP is stainless steelback plate 
EndBlock

Block EPSB IS A PROJECTILE STAINLESS STEEL BAR
EndBlock

Block ERCM is stainless steel tie rod in calorimeter sections
EndBlock

Block ERSM is stainless steel tie rod in shower max
EndBlock

Block EMOD (fsect,lsect) IS ONE MODULEOF THE EM ENDCAP
  Create AND Position ESEC z=section-curr+secwid/2
EndBlock

Block ESEC is a single em section
  Create AND Position ERAD z=length+(cell)/2+esec_deltaz
  Create AND Position EMGT z=length+(gap+cell)/2+esec_deltaz
  Create AND Position ERAD z=length+cell/2+esec_deltaz
EndBlock

Block EMGT is a 30 degree megatile
  Create AND Position EPER alphaz=myPhi
EndBlock

Block EPER is a 5 degree slice of a 30 degree megatile (subsector)
  Create and Position ETAR x=(rbot+rtop)/2ort=yzx
EndBlock

Block ETAR is a single calorimeter cell, containing scintillator, fiber router, etc...
  Create AND Position EALP y=(-megatile+emcs_alincell)/2
  Create AND Position ESCI y=(-megatile+g10)/2+emcs_alincell _
EndBlock

Block ESCI is the active scintillator (polystyrene) layer
EndBlock

Block ERAD is the lead radiator with stainless steel cladding
  Create AND Position ELED 
EndBlock

Block ELED is a lead absorber plate
EndBlock

Block EFLP is the aluminum (aluminium) front plate of the endcap
EndBlock

Block EALP is the thin aluminium plate in calorimeter cell
EndBlock

Block ESPL is the logical volume containing an SMD plane
  Create and Position EXSG alphaz=d3 ncopy=isec kOnly='MANY'
  Create and Position EXSG alphaz=d3 ort=x-y-z ncopy=isec kOnly='MANY'
  Create and Position EXSG alphaz=d3 ncopy=isec kOnly='MANY'
  Create and Position EXSG alphaz=d3 ort=x-y-z ncopy=isec kOnly='MANY'
  Create and Position EXSG alphaz=d3 ncopy=isec kOnly='MANY'
EndBlock

Block EXSG Is another logical volume... this one acutally creates the planes
  Create and Position EXPS kONLY='MANY'
  Create and Position EHMS x=xc y=yc alphaz=-45 kOnly='ONLY'
  Create and Position EBLS x=xc y=yc z=(+esmd_apex/2+esmd_back_layer/2) alphaz=-45 kOnly='ONLY'
  Create and Position EHMS x=xc y=yc alphaz=-45 ort=x-y-z kOnly='ONLY'
  Create and Position EFLS x=xc y=yc z=(-esmd_apex/2-esmd_front_layer/2) alphaz=-45 ort=x-y-z kOnly='ONLY'
EndBlock

Block EHMS defines the triangular SMD strips
Endblock! EHMS

Block EFLS is the layer of material on the front of the SMD planes
EndBlock! EFLS

Block EBLS is the layer of material on the back of the SMD planes
EndBlock! EFLS

Block EXPS is the plastic spacer in the shower maximum section
EndBlock

 

CVS geometry file 

Create ECAL

Block ECAL is one EMC EndCap wheel
  Create and Position EAGA AlphaZ=halfi
EndBlock

Block EAGA is half of wheel air volume forthe EndCap module
  Create and Position EMSS konly='MANY'
  Create and Position ECGH AlphaZ=90 konly='ONLY'
EndBlock

Block EMSS is steel support of the EndCap module
  Create and Position EFLP z=zslice-center+slcwid/2
  Create and Position ECVO z=zslice-center+slcwid/2
  Create and Position ESHM z=zslice-center+slcwid/2
  Create and Position ECVO z=zslice-center+slcwid/2
  Create and Position ESSP z=zslice-center+slcwid/2
  Create ERCM
  Create EPSB
EndBlock

Block ECVO is one of EndCap Volume with megatiles and radiators
  Create and Position EMOD AlphaZ=d3 Ncopy=J_section
EndBlock

Block ESHM is the SHower Maxsection
  Create and Position ESPL z=current
  Create ERSM
Endblock

Block ECGH is air Gap between endcap Half wheels
  Create ECHC
EndBlock

Block ECHC is steel EndCap Half Cover
EndBlock

Block ESSP is Stainless Steelback Plate 
endblock

Block EPSB is Projectile Stainless steel Bar
endblock

Block ERCM is stainless steel tie Rod in CaloriMeter sections
endblock

Block ERSM is stainless steel tie Rod in Shower Max
endblock

Block EMOD is one moduleof the EM EndCap
  Create and Position ESEC z=section-curr+secwid/2
endblock

Block ESEC is a single EM section
  Create and Position ERAD z=len + (cell)/2
  Create and Position EMGT z=len +(gap+cell)/2
  Create and Position ERAD z=len + cell/2
Endblock

Block EMGT is a megatile EM section
  Create and Position EPER AlphaZ=(emcs_Nslices/2-isec+0.5)*dphi
Endblock

Block EPER is a EM subsection period (super layer)
  Create and Position ETAR x=(RBot+RTop)/2ORT=YZX
EndBlock

Block ETAR is one CELL of scintillator, fiber and plastic
  Create and Position EALP y=(-mgt+emcs_AlinCell)/2
  Create and Position ESCI y=(-mgt+G10)/2+emcs_AlinCell _
EndBlock

Block ESCI is the active scintillator (polystyren) layer
endblock

Block ERAD is radiator 
  Create and PositionELED 
endblock

Block ELED is lead absorber Plate 
endblock

Block EFLP is First Aluminium plate 
endblock

Block EALP is ALuminiumPlate in calorimeter cell
endblock

Block ESPL is one of the Shower maxPLanes
  Create and position EXSG AlphaZ=d3Ncopy=isec
  Create and position EXSG AlphaZ=d3Ncopy=isec
  Create and position EXGT z=msecwd AlphaZ=d3
  Create and position EXSG AlphaZ=d3 ORT=X-Y-Z Ncopy=isec
  Create and position EXGT z=-msecwd AlphaZ=d3
  Create and position EXSG AlphaZ=d3Ncopy=isec
  Create and position EXGT z=msecwd AlphaZ=d3
  Create and position EXSG AlphaZ=d3 ORT=X-Y-Z Ncopy=isec
  Create and position EXGT z=-msecwd AlphaZ=d3
Endblock

Block EXSG is the Shower maxGap for scintillator strips
  Create EHMS
endblock

Block EHMS is sHower Max Strip
Endblock

Block EXGT is the G10 layer in the Shower Max
EndBlock

 

Original (ecalgeo.g) file from CVS

Original (ecalgeo.g) file from CVS

******************************************************************************
Module ECALGEO is the EM EndCap Calorimeter GEOmetry
Created   26 jan 1996
Author    Rashid Mehdiyev
*
* Version 1.1, W.J. Llope
*               - changed sensitive medium names...
*
* Version 2.0, R.R. Mehdiyev                                  16.04.97
*               - Support walls included
*               - intercell and intermodule gaps width updated
*               - G10 layers inserted
* Version 2.1, R.R. Mehdiyev                                  23.04.97
*               - Shower Max Detector geometry added          
*               - Variable eta grid step size introduced 
* Version 2.2, R.R. Mehdiyev                                  03.12.97
*               - Eta grid corrected 
*               - Several changes in volume's dimensions
*               - Material changes in SMD
*       
* Version 3.0, O. Rogachevsky                                 28.11.99
*               - New proposal for calorimeter SN 0401
*
* Version 4.1, O.Akio                                          3 Jan 01
*               - Include forward pion detectors

* Version 5.0, O. Rogachevsky                                 20.11.01
*               - FPD is eliminated in this version
*               - More closed to proposal description
*                 of calorimeter and SMD structure
*
******************************************************************************
+CDE,AGECOM,GCONST,GCUNIT.
*
      Content    EAGA,EALP,ECAL,ECHC,ECVO,ECGH,EFLP,EHMS,
                 ELED,EMGT,EMOD,EPER,EPSB,ERAD,ERCM,ERSM,
		 ESHM,ESEC,ESCI,ESGH,ESPL,ESSP,EMSS,
		 ETAR,EXGT,EXSG
*
      Structure  EMCG { Version, int Onoff, int fillMode}

      Structure  EMCS { Type,ZOrig,ZEnd,EtaMin,EtaMax,
                        PhiMin,PhiMax,Offset,
                        Nsupsec,Nsector,Nsection,Nslices,
                        Front,AlinCell,Frplast,Bkplast,PbPlate,LamPlate,
												BckPlate,Hub,Rmshift,SMShift,GapPlt,GapCel,
                        GapSMD,SMDcentr,TieRod(2),Bckfrnt,GapHalf,Cover}
*
      Structure  EETR { Type,Etagr,Phigr,Neta,EtaBin(13)}
*
      Structure  ESEC { Isect, FPlmat, Cell, Scint, Nlayer }
*
      Structure  EMXG {Version,Sapex,Sbase,Rin,Rout,F4}
*
      Structure  EXSE {Jsect,Zshift,Sectype(6)}
*
      Integer    I_section,J_section,Ie,is,isec,i_str,Nstr,Type,ii,jj,
                 cut,fsect,lsect,ihalf,filled
*                       
      Real       center,Plate,Cell,G10,diff,halfi,
                 tan_low,tan_upp,Tanf,RBot,Rtop,Deta,etax,sq2,sq3,
                 dup,dd,d2,d3,rshift,dphi,radiator,orgkeep,endkeep
								 
*
      Real       maxcnt,msecwd,mxgten,curr,Secwid,Section,
                 curcl,EtaTop,EtaBot,slcwid,zslice,Gap,mgt,
                 xleft,xright,yleft,yright,current,
                 rth,len,p,xc,yc,xx,yy,rbotrad,
                 Rdel,dxy,ddn,ddup
                 
    Integer    N
    Parameter (N=12)
* 
    Tanf(etax) = tan(2*atan(exp(-etax)))
* 
* ----------------------------------------------------------------------------
*
* FillMode =1 only 2-5 sectors (in the first half) filled with scintillators 
* FillMode =2 all sectors filled (still only one half of one side)
* FillMode =3 both halves (ie all 12 sectors are filled)

Fill  EMCG                          ! EM EndCAp Calorimeter basic data 
      Version  = 5.0                ! Geometry version 
      OnOff    = 3                  ! Configurations 0-no, 1-west 2-east 3-both
      FillMode = 3                  ! sectors fill mode 

Fill  EMCS                          ! EM Endcap Calorimeter geometry
      Type     = 1                  ! =1 endcap, =2 fpd edcap prototype
      ZOrig    = 268.763            ! calorimeter origin in z
      ZEnd     = 310.007            ! Calorimeter end in z
      EtaMin   = 1.086              ! upper feducial eta cut 
      EtaMax   = 2.0,               ! lower feducial eta cut
      PhiMin   = -90                ! Min phi 
      PhiMax   = 90                 ! Max phi
      Offset   = 0.0                ! offset in x
      Nsupsec  = 6                  ! Number of azimuthal supersectors        
      Nsector  = 30                 ! Number of azimutal sectors (Phi granularity)
      Nslices  = 5                  ! number of phi slices in supersector
      Nsection = 4                  ! Number of readout sections
      Front    = 0.953              ! thickness of the front AL plates
      AlinCell   = 0.02             ! Aluminim plate in cell
      Frplast  = 0.015              ! Front plastic in megatile
      Bkplast  = 0.155              ! Fiber routing guides and back plastic
      Pbplate  = 0.457              ! Lead radiator thickness
      LamPlate  = 0.05              ! Laminated SS plate thickness
      BckPlate = 3.175              ! Back SS plate thickness
      Hub      = 3.81               ! thickness of EndCap hub
      Rmshift  = 2.121              ! radial shift of module
      smshift  = 0.12               ! radial shift of steel support walls
      GapPlt   = 0.3/2              ! HALF of the inter-plate gap in phi
      GapCel   = 0.03/2             ! HALF of the radial inter-cell gap
      GapSMD   = 3.400              ! space for SMD detector
      SMDcentr = 279.542            ! SMD position
      TieRod   = {160.,195}         ! Radial position of tie rods
      Bckfrnt  = 306.832            ! Backplate front Z
      GapHalf  = 0.4                ! 1/2 Gap between halves of endcap wheel
      Cover    = 0.075              ! Cover of wheel half
*      Rmshift  = 2.121              ! radial shift of module
* --------------------------------------------------------------------------
Fill EETR                      ! Eta and Phi grid values
      Type     = 1             ! =1 endcap, =2 fpd
      EtaGr    = 1.0536        ! eta_top/eta_bot tower granularity
      PhiGr    = 0.0981747     ! Phi granularity (radians)
      NEta     = 12            ! Eta granularity
      EtaBin   = {2.0,1.9008,1.8065,1.7168,1.6317,1.5507,1.4738,
                  1.4007,1.3312,1.2651,1.2023,1.1427,1.086}! Eta rapidities
*---------------------------------------------------------------------------
Fill ESEC           ! First EM section
      ISect    = 1                           ! Section number   
      Nlayer   = 1                           ! Number of Sci layers along z
      Cell     = 1.505                       ! Cell full width in z
      Scint    = 0.5                         ! Sci layer thickness
*
Fill ESEC           ! First EM section
      ISect    = 2                           ! Section number   
      Nlayer   = 1                           ! Number of Sci layers along z
      Cell     = 1.505                       ! Cell full width in z
      Scint    = 0.5                         ! Sci layer thickness
*
Fill ESEC           ! Second EM section
      ISect    = 3                           ! Section number
      Nlayer   = 4                           ! Number of Sci layers along z
      Cell     = 1.405                       ! Cell full width in z
      Scint    = 0.4                         ! Sci layer thickness
*
Fill ESEC           ! Third EM section
      ISect    = 4                           ! Section
      Nlayer   = 18                          ! Number of layers along z
      Cell     = 1.405                       ! Cell full width in z
      Scint    = 0.4                         ! Sci layer thickness
*
Fill ESEC           ! 4th EM section
      ISect    = 5                           ! Section
      Nlayer   = 1                           ! Number of  layers along z
      Cell     = 1.505                       ! Cell full width in z
      Scint    = 0.5                         ! Sci layer thickness
*----------------------------------------------------------------------------
Fill EMXG           ! EM Endcap SMD basic data
      Version   = 1                         ! Geometry version
      Sapex     = 0.7                       ! Scintillator strip apex
      Sbase     = 1.0                       ! Scintillator strip base
      Rin = 77.41                           ! inner radius of SMD plane  
      Rout = 213.922                        ! outer radius of SMD plane
      F4 = .15                              ! F4 thickness
*----------------------------------------------------------------------------
Fill EXSE           ! First SMD section
      JSect    = 1                           ! Section number
      Zshift   = -1.215                      ! Section width
      sectype  = {4,1,0,2,1,0}               ! 1-V,2-U,3-cutV,4-cutU    
*
Fill EXSE           ! Second SMD section
      JSect    = 2                           ! Section number   
      Zshift   = 0.                          ! Section width
      sectype  = {0,2,1,0,2,3}               ! 1-V,2-U,3-cutV,4-cutU    
*
Fill EXSE           ! Third SMD section
      JSect    = 3                           ! Section number   
      Zshift   = 1.215                       ! Section width
      sectype  = {1,0,2,1,0,2}               ! 1-V,2-U,3-cutV,4-cutU    

*----------------------------------------------------------------------------
*
      Use    EMCG
*
      sq3 = sqrt(3.)
      sq2 = sqrt(2.)

      prin1 emcg_version 
        ('ECALGEO version ', F4.2)

* Endcap
      USE EMCS type=1
      USE EETR type=1
      orgkeep =  emcs_ZOrig
      endkeep =  emcs_ZEnd
      if(emcg_OnOff>0) then
        diff = 0.0
        center  = (emcs_ZOrig+emcs_ZEnd)/2
        Tan_Upp = tanf(emcs_EtaMin)
        Tan_Low = tanf(emcs_EtaMax)
        rth  = sqrt(1. + Tan_Low*Tan_Low)
        rshift  = emcs_Hub * rth
        dup=emcs_Rmshift*Tan_Upp
        dd=emcs_Rmshift*rth
        d2=rshift + dd
        radiator  = emcs_Pbplate + 2*emcs_LamPlate
*       d3=emcs_Rmshift-2*emcs_smshift
        dphi = (emcs_PhiMax-emcs_PhiMin)/emcs_Nsector
        Create ECAL
        if (emcg_OnOff==1 | emcg_OnOff==3) then
             Position ECAL in CAVE z=+center
        endif
        if (emcg_OnOff==2 | emcg_OnOff==3) then
             Position ECAL in CAVE z=-center ThetaZ=180
        endif

        if(section > emcs_Zend) then
          prin0 section,emcs_Zend
          (' ECALGEO error: sum of sections exceeds maximum ',2F12.4)
        endif
        prin1 section
        (' EndCap calorimeter total depth ',F12.4)
      endif
 
      prin1
        ('ECALGEO finished')
*
* ----------------------------------------------------------------------------
Block ECAL is one EMC EndCap wheel
      Material  Air
      Medium    standard
      Attribute ECAL   seen=1 colo=7                            !  lightblue
      shape     CONE   dz=(emcs_Zend-emcs_ZOrig)/2,
                Rmn1=orgkeep*Tan_Low-d2 Rmn2=endkeep*Tan_Low-d2,
                Rmx1=orgkeep*Tan_Upp+dup Rmx2=endkeep*Tan_Upp+dup


      do ihalf=1,2
	 filled=1
	 halfi = -105 + (ihalf-1)*180
         if (ihalf=2 & emcg_FillMode<3) filled = 0	

         Create and Position EAGA  AlphaZ=halfi

      enddo
*
			
EndBlock
* ----------------------------------------------------------------------------
Block EAGA is half of wheel air volume for  the EndCap module
      Attribute EAGA      seen=1    colo=1   serial=filled           ! black
                        
      Material  Air
      shape     CONS   dz=(emcs_Zend-emcs_ZOrig)/2,
                Rmn1=orgkeep*Tan_Low-d2 Rmn2=endkeep*Tan_Low-d2,
                Rmx1=orgkeep*Tan_Upp+dup Rmx2=endkeep*Tan_Upp+dup,
                phi1=emcs_PhiMin phi2=emcs_PhiMax

        if (filled=1) then
          Create and Position EMSS  konly='MANY'
      		curr = orgkeep ; curcl = endkeep
      		Create and position ECGH  AlphaZ=90 konly='ONLY'
				endif


EndBlock

* ----------------------------------------------------------------------------
Block EMSS is steel support of the EndCap module
      Attribute EMSS      seen=1    colo=1              ! black
                        
      Material  Iron
      shape     CONS   dz=(emcs_Zend-emcs_ZOrig)/2,
                Rmn1=orgkeep*Tan_Low-d2 Rmn2=endkeep*Tan_Low-d2,
                Rmx1=orgkeep*Tan_Upp+dup Rmx2=endkeep*Tan_Upp+dup,
                phi1=emcs_PhiMin phi2=emcs_PhiMax

      zslice = emcs_ZOrig
      prin1 zslice
      (' Front Al plane starts at:  ',F12.4)
      slcwid  = emcs_Front
      Create and Position EFLP  z=zslice-center+slcwid/2
      zslice = zslice + slcwid
                        
      prin1 zslice
      (' First calorimeter starts at:  ',F12.4)

      fsect = 1; lsect = 3

			slcwid = emcs_SMDcentr - emcs_GapSMD/2 - zslice
*
       Create and Position ECVO  z=zslice-center+slcwid/2

      slcwid  = emcs_GapSMD
      zslice = emcs_SMDcentr - emcs_GapSMD/2

			prin1 section,zslice
      (' 1st calorimeter ends, SMD starts at:  ',2F10.5)

      Create and Position ESHM  z=zslice-center+slcwid/2
      zslice = zslice + slcwid

      prin1 zslice
      ('  SMD ends at:  ',F10.5)
*
      slcwid = 0
      fsect = 4; lsect = 5
      do I_section =fsect,lsect
        USE ESEC Isect=I_section  
        Slcwid  = slcwid + esec_cell*esec_Nlayer
      enddo

			slcwid = emcs_bckfrnt - zslice

*
      Create and Position ECVO  z = zslice-center+slcwid/2

      zslice = emcs_bckfrnt

			prin1 section,zslice
      (' 2nd calorimeter ends, Back plate starts at:  ',2F10.5)

      slcwid  = emcs_BckPlate
*
         Create and Position ESSP    z=zslice-center+slcwid/2
         zslice = zslice + slcwid
      prin1 zslice
      (' BackPlate ends at:  ',F10.5)

        slcwid = emcs_Zend-emcs_ZOrig
        Create ERCM

				do i_str = 1,2
					do is = 1,5
				  	xx = emcs_phimin + is*30
						yy = xx*degrad
						xc = cos(yy)*emcs_TieRod(i_str)
						yc = sin(yy)*emcs_TieRod(i_str)
        		Position ERCM z=0 x=xc y=yc  
					enddo
				enddo

        rth = orgkeep*Tan_Upp+dup + 2.5/2
				xc = (endkeep - orgkeep)*Tan_Upp
				len = .5*(endkeep + orgkeep)*Tan_Upp + dup + 2.5/2
				yc = emcs_Zend-emcs_ZOrig
				p = atan(xc/yc)/degrad

				Create EPSB
				do is = 1,6
				  xx = -75 + (is-1)*30
					yy = xx*degrad
					xc = cos(yy)*len
					yc = sin(yy)*len
        	Position EPSB x=xc y=yc  AlphaZ=xx
				enddo

EndBlock
* ----------------------------------------------------------------------------
Block ECVO is one of EndCap Volume with megatiles and radiators
      Material  Air
      Attribute ECVO   seen=1 colo=3                            ! green
      shape     CONS   dz=slcwid/2,
                Rmn1=zslice*Tan_Low-dd Rmn2=(zslice+slcwid)*Tan_Low-dd,
                Rmx1=zslice*Tan_Upp+dup Rmx2=(zslice+slcwid)*Tan_Upp+dup

      do J_section = 1,6
			if (1 < J_section < 6 | emcg_FillMode > 1)then
			 filled = 1
			else
			 filled = 0
			endif
			d3 = 75 - (J_section-1)*30
      Create and Position EMOD AlphaZ=d3   Ncopy=J_section
			enddo

*

EndBlock
* ----------------------------------------------------------------------------
Block ESHM  is the SHower Max  section
*
      Material  Air 
      Attribute ESHM   seen=1   colo=4                  !  blue
      Shape     CONS   dz=SlcWid/2,
          rmn1=zslice*Tan_Low-dd,
          rmn2=(zslice+slcwid)*Tan_Low-dd,
          rmx1=(zslice)*Tan_Upp+dup,
          rmx2=(zslice+slcwid)*Tan_Upp+dup,
          phi1=emcs_PhiMin phi2=emcs_PhiMax

      USE EMXG Version=1
      maxcnt = emcs_SMDcentr
          prin1 zslice,section,center
          (' Z start for SMD,section:  ',3F12.4)
*
        do J_section = 1,3
         USE EXSE Jsect=J_section
*
          current = exse_Zshift
          secwid  = emxg_Sapex + 2.*emxg_F4
          section = maxcnt + exse_zshift
          prin1 j_section,current,section,secwid
          (' layer, Z, width :  ',i3,3F12.4)
          rbot=section*Tan_Low
          rtop=section*Tan_Upp
          prin1 j_section,rbot,rtop
          (' layer, rbot,rtop :  ',i3,2F12.4)
          Create and position ESPL z=current
*
        end do

        Create ERSM
				do i_str = 1,2
					do is = 1,5
				  	xx = emcs_phimin + (is)*30
						yy = xx*degrad
						xc = cos(yy)*emcs_TieRod(i_str)
						yc = sin(yy)*emcs_TieRod(i_str)
        		Position ERSM z=0 x=xc y=yc  
					enddo
				enddo

Endblock
* ----------------------------------------------------------------------------
Block ECGH is air Gap between endcap Half wheels
      Material  Air
      Medium    standard
      Attribute ECGH   seen=0 colo=7                            !  lightblue
      shape     TRD1   dz=(emcs_Zend-emcs_ZOrig)/2,
                dy =(emcs_gaphalf+emcs_cover)/2,
                dx1=orgkeep*Tan_Upp+dup,
                dx2=endkeep*Tan_Upp+dup
                

      rth = emcs_GapHalf + emcs_cover
			xx=curr*Tan_Low-d2
			xleft = sqrt(xx*xx - rth*rth)
			yy=curr*Tan_Upp+dup
			xright = sqrt(yy*yy - rth*rth)
			secwid = yy - xx
			xx=curcl*Tan_Low-d2
			yleft = sqrt(xx*xx - rth*rth)
			yy=curcl*Tan_Upp+dup
			yright = sqrt(yy*yy - rth*rth)
			slcwid = yy - xx
      xx=(xleft+xright)/2
      yy=(yleft + yright)/2
			xc = yy - xx
			len = (xx+yy)/2
			yc = curcl - curr
			p = atan(xc/yc)/degrad
      rth = -(emcs_GapHalf + emcs_cover)/2
      Create  ECHC
      Position ECHC  x=len y=rth
      Position ECHC  x=-len y=rth AlphaZ=180

EndBlock
* ----------------------------------------------------------------------------
Block ECHC is steel EndCap Half Cover
      Attribute ECHC      seen=1    colo=1              ! black
                        
      Material  Iron
      shape     TRAP   dz=(curcl-curr)/2,
			          thet=p,
                bl1=secwid/2,
                tl1=secwid/2,
                bl2=slcwid/2,
                tl2=slcwid/2,
                h1=emcs_cover/2 h2=emcs_cover/2,
                phi=0  alp1=0 alp2=0
EndBlock
* ----------------------------------------------------------------------------
Block ESSP  is Stainless Steel  back Plate 
*
      Material  Iron      
      Attribute ESSP   seen=1  colo=6 fill=1    
      shape     CONS   dz=emcs_BckPlate/2,
                Rmn1=zslice*Tan_Low-dd Rmn2=(zslice+slcwid)*Tan_Low-dd,
                Rmx1=zslice*Tan_Upp+dup Rmx2=(zslice+slcwid)*Tan_Upp+dup,
                phi1=emcs_PhiMin phi2=emcs_PhiMax
endblock
* ----------------------------------------------------------------------------
Block EPSB  is Projectile Stainless steel Bar
*
      Material  Iron      
      Attribute EPSB   seen=1  colo=6 fill=1    
      shape     TRAP   dz=(emcs_Zend-emcs_ZOrig)/2,
			          thet=p,
                bl1=2.5/2,
                tl1=2.5/2,
                bl2=2.5/2,
                tl2=2.5/2,
                h1=2.0/2  h2=2.0/2,
                phi=0  alp1=0 alp2=0
endblock
* ----------------------------------------------------------------------------
Block ERCM  is stainless steel tie Rod in CaloriMeter sections
*
      Material  Iron      
      Attribute ERSM   seen=1  colo=6 fill=1    
      shape     TUBE   dz=slcwid/2,
                rmin=0,
                rmax=1.0425  !    nobody knows exactly
endblock
* ----------------------------------------------------------------------------
Block ERSM  is stainless steel tie Rod in Shower Max
*
      Material  Iron      
      Attribute ERSM   seen=1  colo=6 fill=1    
      shape     TUBE   dz=slcwid/2,
                rmin=0,
                rmax=1.0425
endblock
* ----------------------------------------------------------------------------
Block EMOD is one module  of the EM EndCap
      Attribute EMOD      seen=1    colo=3  serial=filled         ! green
      Material  Air
      Shape     CONS   dz=slcwid/2,
           phi1=emcs_PhiMin/emcs_Nsupsec,
           phi2=emcs_PhiMax/emcs_Nsupsec,
           Rmn1=zslice*Tan_Low-dd  Rmn2=(zslice+slcwid)*Tan_Low-dd,
           Rmx1=zslice*Tan_Upp+dup Rmx2=(zslice+slcwid)*Tan_Upp+dup
*
*    Running parameter 'section' contains the position of the current section
*     It should not be modified in daughters, use 'current' variable instead.
*     SecWid is used in all 'CONS' daughters to define dimensions.
*
*
        section = zslice
        curr = zslice + slcwid/2

        Do I_section =fsect,lsect

         USE ESEC Isect=I_section  
*
         Secwid  = esec_cell*esec_Nlayer
         if (I_section = 3 | I_section = 5) then   ! no last radiator 
           Secwid  = Secwid - radiator
         else if (I_section = 4) then         ! add one more radiator 
           Secwid  = Secwid - esec_cell + radiator
         endif  
         Create and position ESEC      z=section-curr+secwid/2
         section = section + secwid
* 
      enddo
endblock
* ----------------------------------------------------------------------------
Block ESEC is a single EM section
      Attribute ESEC   seen=1    colo=1 serial=filled
      Material Air
      Medium standard
*
      Shape     CONS  dz=secwid/2,  
                rmn1=(section-diff)*Tan_Low-dd,
								rmn2=(section+secwid-diff)*Tan_Low-dd,
                rmx1=(section-diff)*Tan_Upp+dup,
								rmx2=(section+secwid-diff)*Tan_Upp+dup
*
			len = -secwid/2
      current = section
			mgt = esec_scint + emcs_AlinCell _
			       + emcs_FrPlast + emcs_BkPlast
      gap = esec_cell - radiator - mgt
      prin2 I_section,section
      (' ESEC:I_section,section',i3,F12.4)

      Do is = 1,esec_Nlayer
			
* define actual  cell thickness:         
        Cell = esec_cell
				plate = radiator
*
        if (is=nint(esec_Nlayer) & (I_section = 3 | I_section = 5)) then  
         Cell = mgt + gap
         Plate=0
        else if (I_section = 4 & is = 1) then    ! radiator only
         Cell = radiator  
        endif
*                
        prin2 I_section,is,len,cell,current
        (' ESEC:I_section,is,len,cell,current  ',2i3,3F12.4)

      	if (I_section = 4 & is = 1) then       ! radiator only
			  	cell = radiator + .14
     			Create and Position    ERAD     z=len + (cell)/2
        	len = len + cell
        	current = current + cell
      	else
          cell = mgt
					if(filled = 1) then
          	Create and Position EMGT	z=len +(gap+cell)/2
            xx = current + (gap+cell)/2
            prin2 I_section,is,xx
            (' MEGA  I_section,is ',2i3,F10.4)						
					endif
        	len = len + cell + gap
        	current = current + cell + gap

      		if (Plate>0) then
				  	cell = radiator
      			Create and Position    ERAD     z=len + cell/2
          	len = len + cell
          	current = current + cell
      		end if
        end if
      end do 
Endblock
* ----------------------------------------------------------------------------
Block EMGT is a megatile EM section
      Attribute EMGT   seen=1  colo=1 
      Material Air
      Medium standard
*
      Shape     CONS  dz=mgt/2,
      rmn1=(current-diff)*Tan_Low-dd,  rmn2=(current+mgt-diff)*Tan_Low-dd,
      rmx1=(current-diff)*Tan_Upp+dup, rmx2=(current+mgt-diff)*Tan_Upp+dup

      if (I_section=1 | I_section=2 | I_section=5) then
         Call GSTPAR (ag_imed,'CUTGAM',0.00001)
         Call GSTPAR (ag_imed,'CUTELE',0.00001)
      else
         Call GSTPAR (ag_imed,'CUTGAM',0.00008)
         Call GSTPAR (ag_imed,'CUTELE',0.001)
         Call GSTPAR (ag_imed,'BCUTE',0.0001)
      end if
*
      Do isec=1,nint(emcs_Nslices)
         Create and Position EPER AlphaZ=(emcs_Nslices/2-isec+0.5)*dphi
      End Do 
Endblock
*---------------------------------------------------------------------------
Block EPER  is a EM subsection period (super layer)
*
      Material  POLYSTYREN
      Attribute EPER   seen=1  colo=1
      Shape     CONS  dz=mgt/2, 
                phi1=emcs_PhiMin/emcs_Nsector,
                phi2=+emcs_PhiMax/emcs_Nsector,
                rmn1=(current-diff)*Tan_Low-dd,
								rmn2=(current+mgt-diff)*Tan_Low-dd,
                rmx1=(current-diff)*Tan_Upp+dup,
								rmx2=(current+mgt-diff)*Tan_Upp+dup
* 
      curcl = current+mgt/2 
      Do ie = 1,nint(eetr_NEta)
        EtaBot  = eetr_EtaBin(ie)
        EtaTop  = eetr_EtaBin(ie+1)

          RBot=(curcl-diff)*Tanf(EtaBot)
*
        if(Plate > 0) then         ! Ordinary Sci layer
         RTop=min((curcl-diff)*Tanf(EtaTop), _
                    ((current-diff)*Tan_Upp+dup))
        else                     ! last Sci layer in section
         RTop=min((curcl-diff)*Tanf(EtaTop), _
                    ((current-diff)*Tan_Upp+dup))
        endif
        check RBot<RTop
*
        xx=tan(pi*emcs_PhiMax/180.0/emcs_Nsector)
        yy=cos(pi*emcs_PhiMax/180.0/emcs_Nsector)

        Create and Position  ETAR    x=(RBot+RTop)/2  ORT=YZX
        prin2 ie,EtaTop,EtaBot,rbot,rtop
        (' EPER : ie,EtaTop,EtaBot,rbot,rtop ',i3,4F12.4)
      enddo
*
EndBlock
*  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Block ETAR is one CELL of scintillator, fiber and plastic
*
      Attribute ETAR   seen=1  colo=4                           ! blue
*     local z goes along the radius, y is the thickness
      Shape     TRD1   dy=mgt/2   dz=(RTop-RBot)/2,
           dx1=RBot*xx-emcs_GapCel/yy,
           dx2=RTop*xx-emcs_GapCel/yy
*
        Create and Position EALP          y=(-mgt+emcs_AlinCell)/2
      	G10 = esec_scint
      	Create and Position    ESCI       y=(-mgt+G10)/2+emcs_AlinCell _
				                                            +emcs_FrPlast
EndBlock
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Block ESCI  is the active scintillator (polystyren) layer  
*
  Material  POLYSTYREN
      Material  Cpolystyren   Isvol=1
      Attribute ESCI   seen=1   colo=7   fill=0         ! lightblue
*     local z goes along the radius, y is the thickness
      Shape     TRD1   dy=esec_scint/2,
			                 dz=(RTop-RBot)/2-emcs_GapCel
      Call GSTPAR (ag_imed,'CUTGAM',0.00008)
      Call GSTPAR (ag_imed,'CUTELE',0.001)
      Call GSTPAR (ag_imed,'BCUTE',0.0001)
      Call GSTPAR (ag_imed,'CUTNEU',0.001)
      Call GSTPAR (ag_imed,'CUTHAD',0.001)
      Call GSTPAR (ag_imed,'CUTMUO',0.001)
* define Birks law parameters
      Call GSTPAR (ag_imed,'BIRK1',1.)
      Call GSTPAR (ag_imed,'BIRK2',0.013)
      Call GSTPAR (ag_imed,'BIRK3',9.6E-6)
*     
       HITS ESCI   Birk:0:(0,10)  
*                  xx:16:H(-250,250)   yy:16:(-250,250)   zz:16:(-350,350),
*                  px:16:(-100,100)    py:16:(-100,100)   pz:16:(-100,100),
*                  Slen:16:(0,1.e4)    Tof:16:(0,1.e-6)   Step:16:(0,100),
*                  none:16:         
endblock
* ----------------------------------------------------------------------------
Block ERAD  is radiator 
*
      Material  Iron
      Attribute ERAD   seen=1  colo=6 fill=1            ! violet
      Shape     CONS  dz=radiator/2, 
                rmn1=(current)*Tan_Low-dd,
								rmn2=(current+cell)*Tan_Low-dd,
                rmx1=(current)*Tan_Upp+dup,
								rmx2=(current+radiator)*Tan_Upp+dup

      		Create and Position    ELED     

endblock
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Block ELED  is lead absorber Plate 
*
      Material  Lead
      Attribute ELED   seen=1   colo=4  fill=1
      Shape     TUBS  dz=emcs_Pbplate/2,  
                rmin=(current)*Tan_Low,
								rmax=(current+emcs_Pbplate)*Tan_Upp,

      Call GSTPAR (ag_imed,'CUTGAM',0.00008)
      Call GSTPAR (ag_imed,'CUTELE',0.001)
      Call GSTPAR (ag_imed,'BCUTE',0.0001)
      Call GSTPAR (ag_imed,'CUTNEU',0.001)
      Call GSTPAR (ag_imed,'CUTHAD',0.001)
      Call GSTPAR (ag_imed,'CUTMUO',0.001)

endblock
* ----------------------------------------------------------------------------
Block EFLP  is First Aluminium plate 
*
      Material  Aluminium
      Attribute EFLP   seen=1  colo=3 fill=1                    ! green
      shape     CONS   dz=emcs_Front/2,
                Rmn1=68.813 Rmn2=68.813,
                Rmx1=(zslice-diff)*Tan_Upp+dup,
								Rmx2=(zslice + slcwid-diff)*Tan_Upp+dup,
                phi1=emcs_PhiMin phi2=emcs_PhiMax


endblock
* ----------------------------------------------------------------------------
Block EALP  is ALuminium  Plate in calorimeter cell
*
      Material  Aluminium
      Material  StrAluminium isvol=0
      Attribute EALP   seen=1  colo=1
      Shape     TRD1   dy=emcs_AlinCell/2  dz=(RTop-RBot)/2
      Call GSTPAR (ag_imed,'CUTGAM',0.00001)
      Call GSTPAR (ag_imed,'CUTELE',0.00001)
      Call GSTPAR (ag_imed,'LOSS',1.)
      Call GSTPAR (ag_imed,'STRA',1.)
endblock
* ----------------------------------------------------------------------------
Block ESPL  is one of the Shower max  PLanes
*
      Material  Air 
      Attribute ESPL   seen=1   colo=3                  !  blue
      Shape     TUBS   dz=SecWid/2,
                rmin=section*Tan_Low-1.526,
                rmax=(section-secwid/2)*Tan_Upp+dup,
                phi1=emcs_PhiMin phi2=emcs_PhiMax

      USE EMXG Version=1
      msecwd = (emxg_Sapex+emxg_F4)/2
			
      do isec=1,6
	 cut=1
  	 d3 = 75 - (isec-1)*30
	 if (exse_sectype(isec) = 0 | (emcg_FillMode=1 & (isec=6 | isec=1))) then
 	    cut = 0
            Create and position EXSG AlphaZ=d3              Ncopy=isec
	 else if(exse_sectype(isec) = 1) then               !   V
            Create and position EXSG AlphaZ=d3              Ncopy=isec
            Create and position EXGT z=msecwd AlphaZ=d3
	 else if(exse_sectype(isec) = 2) then               !   U
            Create and position EXSG AlphaZ=d3 ORT=X-Y-Z   Ncopy=isec
            Create and position EXGT z=-msecwd AlphaZ=d3
	 else if(exse_sectype(isec) = 3) then               !  cut V
	    cut=2
            Create and position EXSG AlphaZ=d3              Ncopy=isec
            Create and position EXGT z=msecwd AlphaZ=d3
	 else if(exse_sectype(isec) = 4) then               !  cut U 
	    cut=2
            Create and position EXSG AlphaZ=d3 ORT=X-Y-Z   Ncopy=isec
            Create and position EXGT z=-msecwd AlphaZ=d3
	 endif
      enddo

Endblock
* ----------------------------------------------------------------------------
Block EXSG  is the Shower max  Gap for scintillator strips
*
      Attribute EXSG   seen=1   colo=7   serial=cut     ! black
      Material  Air   
      Shape     TUBS   dz=SecWid/2,
                rmin=section*Tan_Low-1.526,
                rmax=(section-secwid/2)*Tan_Upp+dup,
                phi1=emcs_PhiMin/emcs_Nsupsec,
                phi2=emcs_PhiMax/emcs_Nsupsec
*
      Rbot = emxg_Rin
      Rtop = emxg_Rout

      if(cut > 0) then
      if(cut = 1) then
      	Rdel = 3.938
       	Nstr = 288
			else
      	Rdel = -.475
       	Nstr = 285
			endif
			rth = .53*rdel        ! .53 --- tentatavily
    	ddn = sq3*1.713 + Rdel  
    	ddup = .5*1.846 + 1.713 
       prin2 Rbot,Rtop,Nstr
       (' EXSG: Rbot,Rtop,Nstr',2F12.4,I5)
			 mgt = emxg_Sbase + .01
    	do i_str = 1,nstr
        p = .5*(i_str-1)*mgt + 41.3655
*
        if (p <= (.5*rbot*sq3 + rth)) then
           dxy = 1.9375*sq2
           xleft = .5*sq2*p*(sq3 + 1.) - dxy
           yleft = .5*sq2*p*(sq3 - 1.) - dxy 
           yright = .5*sq2*(sqrt( rbot*rbot - p*p) - p)
           xright = sq2*p + yright
        else if ((.5*rbot*sq3  + rth) < p <= (.5*Rtop + 1.5)) then 
           prin2 i_str,p
           (' EXSG: 2 - -i_str,p:',i3,F12.4)
           dxy = 1.9375*sq2
           xleft = .5*sq2*p*(sq3 + 1.) - dxy
           yleft = .5*sq2*p*(sq3 - 1.) - dxy 
					 dxy = rdel*sq2/sq3
           yright = .5*sq2*p*(1.- 1./sq3)
           xright = sq2*p - yright - dxy
           yright = -yright - dxy
        else if (p > (.5*rtop +1.5)) then
           prin2 i_str,p
           (' EXSG: 3 - - i_str,p:',i3,F12.4)
           yleft = (sqrt(rtop*rtop - p*p) - p)/sq2
           xleft = sq2*p + yleft
					 dxy = rdel*sq2/sq3
           yright = .5*sq2*p*(1.- 1./sq3)
           xright = sq2*p - yright - dxy
           yright = -yright - dxy
           dxy = 0. 
           if ((.5*sq3*160.- ddn) < p <= (.5*sq3*160.+ ddup) ) then
             prin2 i_str,p
             (' EXSG: 4 - - i_str,p:',i3,F12.4)
						 xc = .5*(sq3*160.+1.846)
						 yc = xc - .5*sq3*1.713
           if (p > yc) then
             dxy = .5*sq2*(2/sq3*rdel + .5*sq3*1.846 +_
								   sqrt(1.713*1.713 - (p-xc)*(p-xc)))
					 else
             dxy = sq2/sq3*(p - .5*sq3* 160. + ddn)
					 endif
           else if ((.5*sq3*195.- ddn) < p <= (.5*sq3*195. + ddup) ) then
             prin2 i_str,p
             (' EXSG: 5 - - i_str,p:',i3,F12.4)
						 xc = .5*(sq3*195.+1.846)
						 yc = xc - .5*sq3*1.713
           if (p > yc) then
             dxy = .5*sq2*(2/sq3*rdel + .5*sq3*1.846 +_
								   sqrt(1.713*1.713 - (p-xc)*(p-xc)))
					 else
             dxy = sq2/sq3*(p - .5*sq3*195. + ddn)
					 endif
           endif
             xright = xright + dxy
             yright = yright + dxy
          endif

          dxy = section*Tan_Upp - Rtop
          xc = .5*(xright+xleft) + dxy
          yc = .5*(yright+yleft)
          xx = .5*sq2*(xleft+yleft)
          yy = .5*sq2*(xright+yright)
          len = xx-yy
           prin2 i_str,p,yy,xx,len,xc,yc
           (' EXSG: i_str,x,y1,y2,len,xc,yc:',i3,6F12.4)
*
       	 Create  EHMS
      	 if (mod(i_str,2) != 0 ) then                     
          	 Position EHMS  x=xc y=yc AlphaZ=-45
      	 else
          	 Position EHMS  x=xc y=yc AlphaZ=-45 ORT=X-Y-Z
      	 endif
        end do
     	 endif


*     dcut exsg z 0 0 10 0.1 0.1
*     dcut exsg y 0 10 -50 0.7 0.7

endblock
* ----------------------------------------------------------------------------
Block EHMS is  sHower Max Strip
*
      Material  POLYSTYREN
      Material  Cpolystyren   Isvol=1
      Attribute EHMS      seen=1    colo=2  serial=cut          ! red
      Shape     TRD1 dx1=0 dx2=emxg_Sbase/2 dy=len/2 dz=emxg_Sapex/2
      Call GSTPAR (ag_imed,'CUTGAM',0.00008)
      Call GSTPAR (ag_imed,'CUTELE',0.001)
      Call GSTPAR (ag_imed,'BCUTE',0.0001)
* define Birks law parameters
      Call GSTPAR (ag_imed,'BIRK1',1.)
      Call GSTPAR (ag_imed,'BIRK2',0.0130)
      Call GSTPAR (ag_imed,'BIRK3',9.6E-6)
*
       HITS EHMS     Birk:0:(0,10)  
*                     xx:16:SH(-250,250)  yy:16:(-250,250)  zz:16:(-350,350),
*                     px:16:(-100,100)    py:16:(-100,100)  pz:16:(-100,100),
*                     Slen:16:(0,1.e4)    Tof:16:(0,1.e-6)  Step:16:(0,100),
*                     none:16:            Eloss:0:(0,10)
* 
Endblock
* ----------------------------------------------------------------------------
Block EXGT  is the G10 layer in the Shower Max  
*
*     G10 is about 60% SiO2 and 40% epoxy
      Component Si    A=28.08  Z=14   W=0.6*1*28./60.
      Component O     A=16     Z=8    W=0.6*2*16./60.
      Component C     A=12     Z=6    W=0.4*8*12./174.
      Component H     A=1      Z=1    W=0.4*14*1./174.
      Component O     A=16     Z=8    W=0.4*4*16./174.
      Mixture   g10   Dens=1.7
      Attribute EXGT   seen=1   colo=7
      Shape     TUBS   dz=emxg_F4/2,
                rmin=(section-diff)*Tan_Low-1.526,
                rmax=(section+msecwd-diff)*Tan_Upp,
                phi1=emcs_PhiMin/emcs_Nsupsec,
                phi2=emcs_PhiMax/emcs_Nsupsec
      Call GSTPAR (ag_imed,'CUTGAM',0.00001)
      Call GSTPAR (ag_imed,'CUTELE',0.00001)
EndBlock
* ----------------------------------------------------------------------------
* ECAL nice views: dcut ecvo x 1       10 -5  .5 .1
*                  draw emdi 105 0 160  2 13  .2 .1
*                  draw emdi 120 180 150  1 14  .12 .12
* ---------------------------------------------------------------------------
end

ecalgeo.g geometry file (Jason edits, g23)

ecalgeo.g geometry file (Jason Webb edits, g23)

 

 

c*****************************************************************************
Module ECALGEO is the EM EndCap Calorimeter GEOmetry
c--
Created   26 jan 1996
Author    Rashid Mehdiyev
c--
c Version 1.1, W.J. Llope
c               - changed sensitive medium names...
c
c Version 2.0, R.R. Mehdiyev                                  16.04.97
c               - Support walls included
c               - intercell and intermodule gaps width updated
c               - G10 layers inserted
c Version 2.1, R.R. Mehdiyev                                  23.04.97
c               - Shower Max Detector geometry added          
c               - Variable eta grid step size introduced 
c Version 2.2, R.R. Mehdiyev                                  03.12.97
c               - Eta grid corrected 
c               - Several changes in volumes dimensions
c               - Material changes in SMD
c       
c Version 3.0, O. Rogachevsky                                 28.11.99
c               - New proposal for calorimeter SN 0401
c
c Version 4.1, O.Akio                                          3 Jan 01
c               - Include forward pion detectors
c
c Version 5.0, O. Rogachevsky                                 20.11.01
c               - FPD is eliminated in this version
c               - More closed to proposal description
c                 of calorimeter and SMD structure
c
c*****************************************************************************
+CDE,AGECOM,GCONST,GCUNIT.
*
      Content    EAGA,EALP,ECAL,ECHC,ECVO,ECGH,EFLP,EHMS,
                 ELED,EMGT,EMOD,EPER,EPSB,ERAD,ERCM,ERSM,
                 ESHM,ESEC,ESCI,ESGH,ESPL,ESSP,EMSS,ETAR,
                 EXGT,EXSG,EXPS,EFLS,EBLS

      Structure  EMCG { Version, int Onoff, int fillMode}

      Structure  EMCS { Version,Type,zorg,zend,EtaMin,EtaMax,
                        PhiMin,PhiMax,Offset,
                        Nsupsec,Nsector,Nsection,Nslices,
                        Front,AlinCell,Frplast,Bkplast,PbPlate,LamPlate,
                        BckPlate,Hub,Rmshift,SMShift,GapPlt,GapCel,
                        GapSMD,SMDcentr,TieRod(2),Bckfrnt,GapHalf,Cover,
                        Rtie,slop}

      Structure  EETR { Type,Etagr,Phigr,Neta,EtaBin(13)}

      Structure  ESEC { Isect, FPlmat, Cell, Scint, Nlayer, deltaz, Jiggle(18) }

      Structure  EMXG {Version,Sapex,Sbase,Rin,Rout,F4}

      Structure  EXSE {Jsect,Zshift,Sectype(6)}

      Structure  ESMD {Version, front_layer, back_layer, spacer_layer, base, apex }

      Integer    I_section,J_section,Ie,is,isec,istrip,Nstr,Type,ii,jj,
                 cut,fsect,lsect,ihalf,filled,i,j,k,i_sector
                       
      Real       center,Plate,Cell,G10,halfi,
                 tan_low,tan_upp,Tanf,RBot,Rtop,Deta,etax,sq2,sq3,
                 dup,dd,d2,d3,rshift,dphi,radiator
								 
      Real       maxcnt,msecwd,mxgten,curr,Secwid,Section,
                 curcl,EtaTop,EtaBot,zwidth,zslice,Gap,megatile,
                 xleft,xright,yleft,yright,current,
                 rth,length,p,xc,yc,xx,yy,rdel,dxy,ddn,ddup

      Real       myPhi
                 
      Integer    N
      Parameter (N=12)

      Tanf(etax) = tan(2*atan(exp(-etax)))
 
c-------------------------------------------------------------------