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PWG Analysis Update

 Update on Run 5 charged pion A_{LL} for Spin PWG meeting.

grid-links, details

to view my cert:

https://pki1.doegrids.org/displayBySerial?op=displayBySerial&serialNumber=22369

 


Jerome's instruction:

(in progress) EEmc Gammas via conversion method, yield estimates for 2009

Abstract:  We estimate the event yields which may be obtained using the conversion method in the 2009 run.
 

1.0 Event Sample and Cuts

Event sample:
 
1. Data from ppLong2
2. All fills after L2gamma EEmc elevated to physics
4. Select trigger ID 137641
 
Cuts:
 
Before extraction:
1. Require candidate to be w/in the EEMC with pT > 5.0 GeV.
2. Isolation cut -- ET / ETR<0.3 > 0.9
3. Charged particle veto (CPV) -- require sum of all preshower-1 tiles w/in R < 0.3 to be == 0
4. Analyzing cut -- sum preshower-2 tiles w/in R < 0.3 is greater than zero (i.e. at least one tile w/ ADC > 3 sigma + ped).
 
After extraction:
5. Require -8 < log(Epost/Esmd) < -2
 

2.0 Monte Carlo

 
Event Sample
1. 125k Single gammas w/ 2006 geometry
2. 125k Single gammas w/ 2009 geometry
3. Thrown w/ vertex width of +/- 30cm
4. Thrown w/ eta range 0.8 to 2.2
5. Thrown w/ 4 muons in event to establish vertex.  Muons thrown w/ eta = -0.25.
6. pT sampled from e^{-0.6} distribution for pT > 5.0 GeV.
 
Analysis:
MuDsts are created from the MC events, and gamma trees are created.  Events are subjected to same analysis cuts as in section 1.0 above.
 

FileCatalog API

This blog will report on modifications made to the FileCatalog API on W13/08 and following weeks. It will serve as self-documentation.

EEmc Gammas via conversion method, systematics III

 

1.0 Fixing the hadronic width parameter

 
Figure 1.1 -- Width of the hadronic background contribution vs pT (see EEmc Gammas via conversion method, systematics II section

EEmc Gammas via conversion method, systematics II

Abstract: The EEmc Gammas via conversion method for extracting single photons should, in principle, have easily quantified systematic uncertainties.  One needs to know only two things -- the efficiency with which the signal and background pass the analyzing cut.  In practice, since we have three sources of background, the systematic uncertainties become more complicated.  We perform an extraction of the gamma yields vs pT, and determine the systematic uncertainties due to the measured efficiencies.
 
Contents:
 

0.0 Data Sample and Cuts

 
Event sample:
 
1. Data from ppLong2
2. All fills after L2gamma EEmc elevated to physics
4. Select trigger ID 137641
 
Cuts:
 
Before extraction:
1. Require candidate to be w/in the EEMC with pT > 5.0 GeV.
2. Isolation cut -- ET / ETR<0.3 > 0.9
3. Charged particle veto -- require sum of all preshower-1 tiles w/in R < 0.3 to be == 0
4. Analyzing cut -- sum preshower-2 tiles w/in R < 0.3 is greater than zero (i.e. at least one tile w/ ADC > 3 sigma + ped).
 
Post Extraction:
5. Extracted yields summed over -8 < D < -2.
 

Papers on proton interferometry

Papers on proton-proton interferometry (just for my record, list is not complete):

  1. "Proton evaporation time scales from longitudinal and transverse two-proton correlation fu

EEmc Gammas via conversion method, determine/cross check efficiencies

Abstract:  In order to use the conversion method, we need to know the efficiencies with which single photons and the different sources of background candidates pass the analyzing cut.  So far we have identified two sources of backgrounds: (1) photonic backgrounds arising from the decay of mesons, e.g. pi0 --> gamma gamma, and (2) neutral hadrons (or charged hadrons which pass the CPV) which hadronize w/in the calorimeter stack.  We should be able to estimate the efficiencies for both of these directly from the data with good precision.  The only parameter in his method which relies on the Monte Carlo is the probability for a single photon to convert in the 1st radiator of the EEmc.

SVT Ladder weighting exercise

The Silicon Vertex Tracking detector (SVT) in STAR was removed from the STAR setup and a weighting exercise was under-taken.

Measurements made on 2008/03/28

SMD Clustering Plots

Below are SMD plots made from 5000 events each of gammas and piminus.  First tower clustering is done by identifying all seed towers with energy > 1 GeV and then finding the 2x2 patch of to