FGT


Graphics 
courtesy 
of J.Kelsey
MIT, 

 

FGT. . . . . . . . . . P H Y S I C S  
goals, publications, presentations

(PowerPoint, PDF, KeyNote, etc. presentations given by members at meetings, conferences, etc.)


FGT . . . . . . . . . . M E E T I N G S   

minutes, calendar
doc-upload: You do not have access to view this node

(list of people to contact for specific areas, general list of people in FGT group)

 

FGT. . . . . . . . . . S I M U L A T I O N S 
specific information on Monte Carlo
geometry, detector response, event samples

 

Hardware 
FGT. . . . . . . . . H A R D W A R E -- D E T E C T O R 
Triple GEM Foils 
Integration - specific information about the integration of FGT into STAR, west support cylinder, etc.

Thermo-model 16 cm
FGT. . . . . . . . . . H A R D W A R E -- E L E C T R O N I C S  electronics, mother board, etc.

FGT . . . . . . . . . . DAQ  readout, DAQ, etc.

FGT. . . . . . . . . . H A R D W A R E -- S L O W C O N T R O L S  

 

FGT. . . . . . . . . . S O F T W A R E 
muDst container, geant hits, DB tables

 

 

FGT . . . . . . . . . . C A L I B R A T I O N
algo1, y2010
FGT . . . . . . . . . . D O C U M E N T S  
proposal,reviews,design notes, tables, responsibilities,etc
(generally text documents related to the FGT)
FGT . . . . . . . . . . A N A L Y S I S
e/h algo Endcap, high-pT tracking
FGT. . . . . . . . . . P H O T O - - G A L L E R Y + PR figures
(useful plots, drawings, pictures, etc. in original format that people can use in presentations)
FGT. . . . . . . . . . I N S T R U C T I O N S  
edit web-page, HPSS I/O
FGT. . . . . . . . . . V A R I A

FGT sub-system web pages use Drupal nodes: 7217, 10145-156.


 

FGT. . . . . . . . . . I N S T R U C T I O N S

  1. You do not have access to view this node
  2. HPSS   HPSS I/O  private/production files
  3. Navigation through FGT web pages  
  4. Guidelines For MIT Tier2 Job Requests For MIT Tier2 Job Requests (Mike)

 

HPSS I/O

 

 


HTAR :  save/restore  private directory (large set of small files) in HPSS

For saving all files in directory 'aaa' on disk to your HPSS target bbb/ccc.tar and keep log file in ~/0x/ddd.log1 (needed if you want to kill/quit the window) do: 
 
cd aaa
du -hs .
htar -cf bbb/ccc.tar file1 file2 fileX* ... >& ~/0x/ddd.log1 &
(wait until job is done, for 50GB make take severa hours)
hsi (goes directly to HPSS, be careful!)
?ls -l  bbb/
?quit (exit hsi)
 
You should see 2 files : ccc.tar & ccc.tar.idx, the size of file ccc.tar should be close to the size of your oryginal directory.
The .tar file shows up immediately but sinking is NOT finished until you see  .idx file.
The log file should contain the string: HTAR: HTAR SUCCESSFUL , no warnings.
However the most reliable way to verify the storage did not failed is to:
 
retrieving files from HPSS  to disk directory eee do:
 
mkdir eee
cd eee
htar -xf bbb/ccc.tar  >& ~/0x/ddd.log2 &
 
Other options of HTAR command are described here: 
       http://drupal.star.bnl.gov/STAR/comp/sofi/hpss/htar

Known problems:

WARNING: htar_PreallocateSpace: HPSS OUT-OF-SPACE error preallocating
**** bytes for file=[/home/salur/myfile.tar]
This is a directory with 350G. Do I have to divide my files into  smaller.
 there is a 60GB max file size limit [when creating tarballs],   Another
limit to be aware of, however, is an 8GB limit on member files

 

 


 Mass restoring of ~100GB files from HPSS using Data Carusel

Prepare input file xxx.hpss with list of source +destination paths for all files  you need, one line per file

Execute the command (at any location at rcas6nnn)

 hpss_user.pl -f xxx.hpss

Wait 10-1000 minutes fro the files to show up at your destination (if all paths are correct)

 

 

 

Instruction for new users uploading FGT documents

Instruction for remote uploading of documents to the common FGT Drupal place to complement missing features of fgt-hn

 


First time setup

  1. You need to login to drupal as you. The password is different than your regular RCF password. If you do not remember Drupal password select 'forgot password' and new one will be sent to you by e-mail
  2. got to the mother-web page:
    http://drupal.star.bnl.gov/STAR/subsys/upgr/fgt/hn-upload-contributions
    you can also navigate: SubSystems --> Detctor Upgrades --> FGT --> FGT-HN Upload
  3. Got to the bottom and select 'Add child page'
  4. Set the following fields:
    * Title: yourName-FGT-HN-Uploads (edit it)
    * Parent: ------FGT-HN-Upload contributions (selectable from menu)
    * STAR: --FGT (selectable)
    * Body: Your Name : list of attachements sent to FGT-HN (edit it, just 1 line)
    Upload a test jpg file using menu at the very bottom of the page. To attache new file, first 'Choose File', next 'Attach'
  5. Finally at the very bottom 'Submit' the whole page to Drupal.
  6. go to the 'mother-page' and you should see:
    * in the upper part your JPG
    * in the lower part (below bold text) your sub-page among other people who already joined, alphabetical order.
    If you can't see your contribution at this point contact me (Jan). Do not try it over - it will add mess to Drupal. If you add more than one page only the first one will be considered

 


Uploading subsequent documents

  1. Login to drupal and go to your sub-page with this test JPEG
  2. Click Edit
  3. scroll down to upload section and add as many documents as needed, one by one
  4. you may change the name of uploaded file - just edit it
  5. Click 'Submit'
  6. go to the 'mother-page' and you should see your new documents listed in chronological order.
  7. Now you can sent an e-mail to FGT-HN referring your new uploaded documents as:
    .... new docs are uploaded to:
    http://drupal.star.bnl.gov/STAR/subsys/upgr/fgt/hn-upload-contributions 
    under myName, files xxx-yyy-jpg and zzz-uuu-mmm.pdf
    

Report to me if there are any problems,
Jan

FGT. . . . . . . . . . P H Y S I C S

  1. Physics motivation
  2. Publications 
  3. Talks
    date person format title occasion
    April 2006 Frank pdf ppt Development of Tracking Detectors with Industrially Produced GEM foils TPC workshop, Berkeley
    October 2006 Frank pdf ppt Development of Tracking Detectors with Industrially Produced GEM Foils IEEE NSS 2006, San Diego, CA, USA
    January 2007 Bernd pdf FGT-Technical implementation, Cost, R&D plan, Schedule  BNL Detector Advisory Committee Meeting
    - - - - -
  4. NIM paper on the Fermilab test beam is now published in NIM. 
    F. Simon et al., Nuclear Instruments and Methods in Physics Research A 598 (2009) 432–438

 


 

FGT. . . . . . . . . . S I M U L A T I O N S

Simulation of physics background for development of e/h algo. ( Physics Background Simulation)  

Selected topics:

 

Physics Background Simulation

Ongoing effort of preparing physics-background samples for developing of e/h discrimination algos for W reconstruction

Existing Framework For FGT Simulations

With the completion of the FGT hardware review, focus must now be made on the creation and implementation of efficient analysis algorithms. To this end a framework for creating simulation files must be established. Here I document the existing framework I created this past summer for a small FGT project.
    The creation of simulation files within STAR is handled in two steps.

  • starsim is called with a PYTHIA kumac, creating a fzd file.
  • The fzd file is converted to a full muDst with the bfc.

The kumac sets all parameters of the underlying physics events, while the bfc handles the fine tuning of the reconstruction of the STAR detector.
    In the following analysis the simulation was split by the underlying physics processes: those producing W bosons and those from QCD 2->2 interactions. Both are produced with the geometry UPGR13 and sqrt(s) = 500 GeV, in accordance with the FGT upgrade. Moreover, each kumac accepts a random number seed to ensure that different jobs are independent of each other.  Specific details are included below,

PYTHIA Settings
  W Hadron
Geometry UPGR13 UPGR13
sqrt(s) 500 GeV 500 GeV
Vertex (mean, variance) 0 cm, 60 cm 0 cm, 60 cm
     
Subprocesses 2, 15, 20, 23, 25, 31 11, 12, 13, 28, 53, 68, 96
CKIN3 10 GeV 10 GeV
CKIN4 None None
Additional Cuts Require electron in the endcap with pT > 15 GeV None
Additional Notes W bosons made explicitly unstable None
     
Events / Job 4000 2000
Cross Section / Job O(103 pb) O(103 pb)
PYTHIA + GSTAR + BFC Running Time / Job O(20 hours) O(16 hours)
PYTHIA  + GSTAR Running Time / Job O(12 hours) O(6 hours)
Memory Used / Job O(1000 MB) O(1500 MB)
Size of Output Files / Job O(2.5 GB) O(2.5 GB)
Once starsim has completed, the files are processed through the bfc with the command

bfc.C\(1,nEvents,"trs ssd upgr13 pixFastSim Idst IAna l0 tpcI fcf Tree logger ITTF Sti StiRnd PixelIT IstIT StiPulls genvtx NoSvtIt SsdIt MakeEvent McEvent geant evoutgeantout IdTruth tags bbcSim emcY2 EEfs big -dstout fzin MiniMcMk McEvOut clearmem","fileName.fzd")

Detailed log files can be found at

/star/institutions/mit/betan/FGT/Logs/

while the existing files are at

/star/institutions/mit/betan/ROOT_Files/FGT/

Attached are the relevant scripts (the _.txt has been added to get around DRUPAL attachment restrictions), although the hardcoded paths are no longer valid.  The master script is submit_simulations.csh, which submits all the others to the RCAS queue star_cas_big.  In particular, W_job.csh and hadron_job.csh are each called with the command line arguments

*_job.csh <em>nEvents fileName randomNumberSeed

The *_job.csh scrips then call the starsim and bfc with the necessary arguments passed as appropriate.

Filtered Simulations For The Development of Electron/Hadron Discrimination Algorithms

Critical to the upcoming flavor physics at STAR is efficient electron identification in the endcap, particularly amongst the dominant charged hadron/meson background.  The development of such discrimination algorithms, however, requires extensive simulations.  To reduce the computational burden of these simulations to a practical level we must modify starsim, reconstructing only those events of interest.

In this case we require electrons and charged hadrons/mesons in the endcap, and by adding a filter to PYTHIA we can ensure that only events matching the this criteria are reconstructed.  Below is a small study showing the significant reduction in computing time gained with this filtering.

The filtered simulations required a charged hadron or meson in the endcap with pT > 15 GeV before GSTAR was allowed to reconstruct the event.  Candidate refers to an event meeting the above requirements in the PYTHIA record, and projected refers to an extrapolation estimate for 80 pb-1.

Hadrons/Mesons Filtered Filtered (Projected) Unfiltered Unfiltered (Projected)
Candidates 10 18,604 10 18,604
Reconstructed GEANT Events 10 18,604 2863 5,326,325
Integrated Luminousity (pb-1) 0.043 80 0.043 80
Starsim Running Time (hours) 0.274 509  7.42  13,817
BFC Running Time (hours) 0.845 1572  24.2  45,023

Looking at the tracks in the GEANT record we see that the filtering worked as described.  Here every charged hadron/meson in every reconstructed event is shown, and in the Filtered sample we see a sharp cutoff at 15 GeV exactly as expected. 

The same analysis can be done for the W boson simulations, here instead requiring an electron(positron) from a W decay in the endcap with pT > 15 GeV.

Ws Filtered Filtered (Projected) Unfiltered Unfiltered (Projected)
Candidates 10  672 10  672
Reconstructed GEANT Events 10 10 357  24,020
Integrated Luminousity (pb-1)  1.189 80  1.189 80
Starsim Running Time (hours)  0.0361  2.42  0.822  55.3
BFC Running Time (hours)  0.0882  5.93  2.807  188.8

Again, comparing the two files shows the desired effects

In both cases the computational demands seem impractical, but one has to remember that this extrapolation is based on the use of a single processor.  Real jobs will be run in parallel, significantly reducing the projected times to more reasonable levels.  Despite the reduction, however, it might still be necessary to reduce the desired integrated luminousity slightly.

Filtering PYTHIA Events In Starsim

Within the STAR framework, simulation files are created with the command starsim which runs both PYTHIA and GEANT.  Unfortunately, this means that there is no straightforward way to filter PYTHIA events before the GEANT reconstruction and producing simulation files for rare events can be very time consuming, as most of the CPU is wasted on the GEANT reconstruction of undesired events.

The trick around this is to modify the PYTHIA libraries themselves.  In particular we want to modify the PYEVNT subroutine which is run during the generation of each PYTHIA event.  Begin by

  •     Checking out a copy of the pythia libraries from cvs
  •     Create a back up of pyevnt.F in case anything goes wrong
  •     Open up pyevnt.F in your favorite text editor
  •     Rename SUBROUTINE PYEVNT to SUBROUTINE PYEVNT_ORG
  •     Now create your own subroutine, SUBROUTINE PYEVNT
  •     Copy the variable declarations and commonblocks from the original PYEVNT

The body of this new subroutine will in general go as the following

while(conditions have not been met)

Call the original PYEVNT
Call any necessary auxillery subroutines
Loop over particles
if(not desired characteristic a) continue
if(not desired characteristic b) continue
...
if(not desired characteristic i) continue
Calculate relevant kinematic variables
Check conditions
Call PYLIST

Note that to avoid too many nested if loops we abort when the first test fails.

For example, consider an analysis requiring a high energy electron in the endcap.  The usual PYTHIA settings allow one to require a high energy electron, but there is no way to restrict its location in the detector.  So in the above pseudocode becomes

while(no high pT electron in the endcap)

Call the original PYEVNT
Loop over particles
if(not electron) continue
Calculate pT
Calculate eta
if(pT < 15) continue
if(eta < 1) continue
if(eta > 2) continue
return
Call PYLIST

The main background to the above is charged hadrons/mesons.  In order to filter these we require that the particle has a charge of +/- 1, that is has the PDG ID of a hadron or a meson, that it has not decayed in the PYTHIA record, and fulfills the kinematic requirements.

while(no high pT jet in the endcap)

Call the original PYEVNT
Loop over the jets at the end of the PYTHIA record
if(not stable) continue
if(charge not equal +/- 1) continue
if(not hadron or meson) continue
Calculate pT
Calculate eta
if(pT < 15) continue
if(eta < 1) continue
if(eta > 2) continue
return
Call PYLIST

Once pyevnt.F has been succussfully modified it must be compiled with cons, and the path to the compiled library itself must be explicitly set in the kumac.  For example,

gexec $STAR_LIB/libpythia_6410.so

must be replaced by

gexec /star/u/username/path_to_directory/.slxx_gccxxxx/lib/name_of_new_pythia_library.so

Examples of modified pyevnt.F files for both the electron example and the jet example are attached, as is a kumac for use with the jet example.

List of available M-C event samples (Jan)

.

M-C Event Samples Available   

  1. General  setup, assumptions
    1. use UPGR13 geometry
    2. run in SL07e
    3. use PPV vertex finder in reco
    4. displace & smear vertex in GEANT in X-Y plane: x0=+1mm, sig=200us, y0=-2mm, sig=200um (except setA)
    5. beam energy sqrt(s)=500 GeV
    6. detectors passed by track thrown at various eta at 3 Z-vertex location of -60, -30 an 0 cm.


  2. setA (produced by Mike @ MIT)
  3. BFC w/ generic vertex finder has ~50% efficiency,

    Vertex distribution: Gauss(Z=0, sigZ=60cm, Z=Y=0, sigX=sigY=0)

     Type of events   total events time per event
     Pythia, minB  400K, 100 jobs  GSTAR: 8.4 sec, BFC ???

    Files location: 80K eve at IUCF disk: /star/institutions/iucf/kocolosk/2008-02-15-fgt-hadron-background

    full sample at MIT ...



     

  4. setB (pilot sample by Jan @ RCF)
  5. Filtering of Pythia events: seed cell =10GeV ET, pair of cells>20 GeV ET,

    particle eta range [0.8,2.2], grid cell size: 0.14 in eta, 9 deg in phi

    BFC w/ PPV vertex finder has ~95% efficiency, SSD, STI not used in tracking

    Vertex distribution: Gauss(Z=-60, sigZ=5cm, Z,Y offset)


    Pythia event generator, 

    BFC chain:" DbV20080310 trs  -ssd upgr13  Idst IAna l0 tpcI fcf -ftpc Tree logger ITTF Sti StiRnd  -IstIT -SvtIt -NoSvtIt SvtCL,svtDb -SsdIt MakeEvent McEvent geant evout geantout IdTruth  bbcSim emcY2 EEfs bigbig -dstout fzin -MiniMcMk McEvOut clearmem -ctbMatchVtx VFPPV eemcDb beamLine"

     Type of events Pythia filter   total events time per event job name file size, MB
      W-events (kumac) 1/6.5  1K, 1 job GSTAR 10 sec, BFC 5.3 sec wElec4 fzd=149, stevent=132, geant=154, McEvent=132, muDst=14
    1:1 , OFF  5K, 1 job - wElec5 -
      QCD-events (kumac) pt=20-30 GeV 1/40  1K, 1 job GSTAR 11 sec, BFC 6.7 sec qcd2 fzd=203, StEvent=157, geant=212, McEvent=172, muDst=17
    1:1, OFF  5K, 1 job - qcd3 -
      QCD-events, scan pt 10...90 GeV varies  100 eve, 1 job - qcd_pt_xx_yy files at ...balewski/2008-FGT-simu/setB-pt-scan/

    Files location:  /star/institutions/iucf/balewski/2008-FGT-simu/setB-pilot/


    Custom code : Pythia, Generic Vertex finder, same location

     

  6.  setC - Pythia macros inspected by Jim: ppQCDprod.kumac & ppWprod.kumac
    Filtering of Pythia events: seed cell =10GeV ET, pair of cells>20 GeV ET,
    particle eta range [0.8,2.2], grid cell size: 0.14 in eta, 9 deg in phi

     
    * setC1: /star/institutions/iucf/balewski/2008-FGT-simu/setC2-pt-0.2inv_pb

    This is LT balanced for 0.2/pb, using your ppQCDprod.kumac

    pt1 pt2 neve
    10    ,15    ,373
    15    ,20    ,1252
    20    ,25    ,2516
    25    ,30    ,3367
    30    ,35    ,2330
    35    ,40    ,1015
    40    ,45    ,705
    45    ,50    ,292
    50    ,55    ,114
    55    ,60    ,67
    60    ,65    ,28
    65    ,70    ,13
    70    ,75    ,8
    75    ,80    ,4
    80    ,85    ,2
    85    ,90    ,1
    90    ,95    ,1
    

     


    * setC2 (only filtered events of various types)

     

     


    * setC3 (filtered vs. not filtered events)

     

     

    * setC4 ( filtered QCD events w/ various partonic PT )

  7. setC5 : QCD events , 3-stage filtering, LT~100/pb

 

evaluation of Pythia Filter for QCD & W events (setC3)

 

Based on setC3 the number of events with reco EM cluster ET>20 GeV is similar for the filtered and unfiltered pythia samples after LT correction - compare yellow & green areas: 

 

------------ From Brian -------

Hi Jan,

I processed the events in setC3 and I put the plots into the
fgt-hn-contributions drupal page. (All plots show unfiltered events on
the left and filtered events on the right).

Transverse energy spectrum for the QCD events:
http://drupal.star.bnl.gov/STAR/system/files/ETspectrumQCD.png

Number of events passing ET>20GeV and ET>20GeV + Eta < 1.7 for QCD
events: http://drupal.star.bnl.gov/STAR/system/files/OPcountsQCD.png

Transverse energy spectrum for the W events:
http://drupal.star.bnl.gov/STAR/system/files/ETspectrumW.png

Number of events passing ET>20GeV and ET>20GeV + Eta < 1.7 for W events:
http://drupal.star.bnl.gov/STAR/system/files/OPcountsW.png

Brian

 

PT scan of Pythia-filter rejection for QCD events ( Jan)

Pythia Filer: cell>10 GeV ET, cluster >20 GeV ET , grid covers Endcap Pythia events

Note, 'live' spreadsheet is attached at the bottom

 

Examples of event filtering for some choices partonic PT ranges:

pt range event counter and pt spectra eta-phi distributions, all pythia tracks and seed distribution

partonic PT 15-20 GeV

Filter=1/760

 

 

partonic PT 40-45 GeV

Filter=1/3.6

 

 

 

partonic PT 75-80 GeV

Filter=1/4.6

 

 

 

 

Practical Pythia Event Filter (Jan)

Filtering of Pythia events preserving those which may fire HT trigger in the Endcap.

Motivation
In order to develop efficient e/h discrimination algo for reco of electrons from Ws it is necessary to generate sizable sample of QCD physics background events with 1e5 or more events triggering Endcap HT >10 GeV. The brute force approach (run PYTHIA+GSTAR+BFC long enough) is investigated by my not succeed due to low yield of events of interests.

Therefore, we are working on the in-fly Pythia events filtering. It must be more complex than accepting events with a single Pythia track above certain threshold because multiple tracks from jet (also hadrons) may deposit in a single tower cumulative energy exceeding the HT threshold even if all tracks have energy below this threshold.

The tricky part is to decide if EEMC response may be large before GSTAR does very time consuming simulation of EM & hadronic showers for the whole event.


Proposed Method (2-stage Pythia filtering)

  • Define : eta range [0.9,2.1], partonPTthres of 5 GeV, jetPTthres of 5 GeV (to be tuned later)
  • Inspect lines 7 & 8 of Pythia record (counting from 1) and drop event if none of partons is within eta range and above parton PT threshold.
    For survived events
  • Define 2D eta-phi grid covering eta [0.9,2.1] and 2pi in phi. Divide it in to cells of size 0.1x0.1. Clear grid for every event.
  • Loop over Pythia record 9..max and drop: partons, gluons, unstable particles, neutrino, muons.
    Retain all stable hadrons, e+, e- within eta range, project particle ET in to the eta-phi grid.
  • find seeds all cells with ET above 1/2 of jetThreshold.
  • for every seed from 8 pairs using every of its neighbors. If any pair ET sum is above jetThreshold event will be accepted and passed to GSTAR and eventually to BFC.

Additional comments:
* for Barrel eta range should be [-0.2,1.2] and cell size 0.05x0.05 in eta x phi.
* the code should be written in F77.
* at any step priority should be given to processing speed vs. program size. E.g. use lookup tables when reasonable.
* provide few QA histos generated with Pythia using HBOOK + kumac to display them


Content of Pythia record

1 proton 1
2 proton 2
3 parton from proton1
4 parton from proton2
5 parton from proton 1 after intial state radiation
6 parton from proton 2 after intial state radiation
7 parton 1 after scatter
8 parton 2 after scatter
9 ... intermediate and final partons/particles
....

 

evaluation of Bates minB sample (Jan)

Evaluation of minB events ample produced by Mike at Bates in January of 2008.

Events characteristic: Pythia MinB events, sqrt(s)=500 GeV, vertex Gauss(0,60cm)

Below you see detectors acquired by e+/e- surrogate :  

  1st pi-,pi+ with pT>2.0 GeV and eta>0.7

FGT disks are located at Z of 70,80,...,110 cm - our best guess location.

3 events samples were chosen based on Geant vertex location of -60, 30, and 0 cm, with margin of +/-10 cm, what leads to smeared FGT disks.  

 

Optimization of FGT disk location


 Several versions of FGT disk geometries has been studied in 2007

as documented  here (disk-based HTML documentation)


 

Z disk location accuracy

Propagation of the Z hit location inaccuracy  on to the error of predicted Rxy location of the Endcap EM shower.

 
Slide 1.  Every FGT disk is mounted only at  only 2 points to the Alu rail r=6mm, disks have R=38 cm, so the leverage arm is 1:63.
The tension from individual (stiff) cables located also at 90 deg vs. Alu rods  could cause a tilt of disks ( during cables assembly or sliding the 6-disk unit to its final position at STAR).
 
Slide 2.  An example of FGT-only reconstructed track. The inset shows there is an intrinsic fluctuation of primary ionization over 3mm in Z, we can't compensate off-line. This sets the scale for accuracy Z-alignment of the disks.
  
Slide 3  shows  systematical displacement of predicted EM shower radial distance at the Endcap due to extreme ionization spread in 2 FGT disks . In reconstruction the mean Z location of FGT disks is used. The predicted radial distance of the reco tracks at Z=SMD  can be off by up to 1.2cm.
This is not that small  but since we will impose isolation cut in EEMC, there should be no other significant energy deposit in calorimeter at much larger radii. Note, the EM shower radii is of 3 cm, but we claim its center will be reco with 1mm accuracy. 
 



 

 

geometry in MC

 Documented evolution of implementation of FGT geometry in GSTAR, started on May, 2008

Our studies are below seen as child pages.

Here are links to other studies

 

1 content of UPGR15, May 2008

 Selected cross sections of UPGR15 geometry, as of May 2008

Fig 1

Fig 2

Fig 3

Fig 4

Fig 5


Fig 5 Realistic geometry from Jim K. model, May 2008

2 UPGR15+FGT as of May 2008

 UPGR15 geometry was modified to match best guess of FGT geometry as of May 2008.

The active FGT area is : Z1=70,..., Z6=120cm, DZ=10 cm, Rin=11.5cm, Rout=37.5 cm 
There is 1cm of additional dead material at Rin & Rout

 


Fig 1. Zvertex=0 cm, green= eta [1.06,2.0]. , red=eta[2.5,4.0]

 

 


Fig 2. Zvertex=+30 cm, green= eta [1.06,2.0]. , red=eta[2.5,4.0]

 

 


Fig 3. Zvertex=-30 cm, green= eta [1.06,2.0]. , red=eta[2.5,4.0]

 


Fig 4. Zoom in on 1 FGT disk.  Detected particle enters from the left, 'active' gas volume has depth of 3mm (between magenta ad blue lines),  FGT strips collect charge on the 1st green line.
 (units in cm)
Zstart = 70.0 ! starting position along Z axis
Z = { 0.0, 10.0, 20.0, 30.0, 40.0, 50.0} ! Z positions for GEM front face
FThk = { 0.05, 0.05, 0.05, 0.05 } ! foil thicknesses inside GEM
SThk = { 0.3, 0.2, 0.2, 0.2 } ! support/spacing thicknesses
SR = 1.0 ! radial size for support

USED material:

 * use aluminized mylar mixture instead of kapton
      Component C5  A=12    Z=6  W=5
      Component H4  A=1     Z=1  W=4
      Component O2  A=16    Z=8  W=2
      Component Al  A=27    Z=13 W=0.2302
      Mixture  ALKAP  Dens=1.432
 
*     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
 
Block FGDO is the mother volume of the individual GEM disks
      Component Ar A=39.95   Z=18.   W=0.9
      Component C  A=12.01   Z=6.    W=0.1*1*12.01/44.01
      Component O  A=16.     Z=8.    W=0.1*2*16./44.01
      Mixture   Ar_mix  Dens=0.0018015
 
Block FGFO describes the GEM foils
      Material ALKAP
Block FGIS describes the inner support or spacer
      Material G10

Fig 4b FGT disk front view in Geant


 

Fig 5. 1st FGT disk by Jim K. as of April, 2008

 


Fig 6. 3 FGT disks by Jim K. as of April, 2008  


Fig 7 Realistic geometry from Jim K. as of May, 2008


Fig 8 Disk material budget, from Doug, as of May, 2008


Fig 9 APV location , from Doug, as of May, 2008


 

 

3 new FGT geometry

 Modified FGT geometry of FGT, June 2008

 Detailed description (PDF) , ver 1

4 compare geom 2007 vs. UPGR16

 

Green dashed lines at eta=1.0,.1.06,2.0

red lines at eta=2.5, 4.0


 geom=2007

 


UPGR16, geom=2010

 


 

Speculative FGT++

another 6 disks are added at the following Z:

 Zstart  =   62.98  ! starting position along Z axis

 Z       = { 5.4, 15.4, 25.4, 35.4, 45.4, 55.4, 75., 90., 105., 120., 135., 150.}  ! Z positions of GEM front face

Green dashed lines at eta=1.0,.1.09,2.0

red lines at eta=2.5, 4.0

 

5 FGT cables in Geant

 Notes,

 



If I want to know the total area for one FGT disk what is the proper multiplier : 4, 28, or 24*28 ?

Within the cable, multipliers for the individual "subcomponents" are in column L.

Then, there are overall 4 cables per FGT disk - the column B tells you number of cables and I-J tells you where they go.

In other words, for instance, overall total copper area in FGT-power cables is
24*(7*5.176E-3+1*3.255E-3) = 0.948 cm^2.

I know you asked to break out with one "line" per cable route - we can do this later but for now there are already a lot of lines... I'll leave them grouped as this and you should look at I-J to decide the lengths and where they are.

By the way, I imagine the "patch" between cone/FGT cables and "external" cables lying on TPC endwheel, through services gap, to crates, occurs somewhere just outside the cone, within the first foot or so.


6 radiation length study for UPGR16 + SSD

Study of the dead material in front and behind FGT.

3 versions of GEANT geometries were investigated:

  • UPGR16 + current SSD w/ current cables
  • UPGR16 w/ 'light' SSD (Alu support structure replaced by carbon, Cu cables replaced by Alu)
  • UPGR16 without SSD, nor SSD cables

Plot below is just example of material using current SSD.

 Many more plots are in attached PDF, in particular figs 2a-c, 3a-c, 4a-c.

7 PR track plots with UPGR16 & fixed barrel

Geometry= UPGR16, 6 FGT disks , fixed barrel geometry.

Single electrons, 20 GeV ET, thrown at eta=0, 0.4, 0.8, 1.2, 1.6, 2.0


Fig 1, Z vertex=0

 


Fig 2, Z vertex=+30 cm

 


Fig 3, Z vertex=-30 cm

 

 

FGT hits fired by backward tracks (Wei-Ming Zhang)

 

           1, MC tracks (eta < -1.3) are thrown backwards and FGT are found fired.
 

             Fig. 1, An events with FGT hits fired by backward tracks (UPGR16)

           2, To investigate with tracks (1.3 |eta| < 3.1) from MC events of RQMD Au-Au 10 GeV
 

            Fig. 2

 

          There are two rows in Fig. 2. Each row has three plots, the left is track multiplicity of events, the middle pt of
      tracks, and the right dE of FGT hits in KeV. The top row is plotted for backward tracks which fire FGT and for fired FGT 
      hits (backward hits). The first two of the bottom are for all backward tracks. The right of the bottom is a dE spectrum
      of FGT hits fired by FORWARD tracks (forward hits).  From Fig. 1, we see
        1, A low level of backward hits  (mult_0/mult_1 = 200 shown in the top left plot)
        2, A relatively large energy loss of backward hits which is 2-3 time larger than that of forward hits.
           This suggests backward tracks which fire FGT have very low speed and deposit more energy than forward MIPs.

         Based on the above, we believe that backward hits in FGT come from multiple scattering.
 

        Fig. 3, Split spectra of the top row of Fig. 2 for individual FGT disks: disk1 (top) disk2 (middle)
               and disk3 (bottome)
 

 

       Fig. 4, Split spectra of the top row of Fig. 2 for individual FGT disks: disk4 (top) disk5 (middle)
               and disk6 (bottome)
 

 

 

 

 

 

 

 

FGT. . . . . . . . . H A R D W A R E -- D E T E C T O R

  1. FGT foil
  2. FGT disk
  3. FGT strip design, gerber screen dumps, 2010-12-20
  4. 6-disk assembly
  5. integration w/ STAR
    date revision format component
    March 2008 ? revXXX? PDF west support cylinder
    March 2008 ? 4.0 ? PDF mounting of FGT foil quadrant

 

Electrostatic Calculations for West Support Cone

 Hi all;
 I've put some results from the latest electrostatic
calculations for the WSC at:
http://hepwww.physics.yale.edu/star/upgrades/WSC-D.ppt
http://hepwww.physics.yale.edu/star/upgrades/WSC-D.pdf
The first page shows the key elements of the model and
the changes from previous versions:
- All edges of the WSC are radius'ed with 2 cm
- The resistor chain is now from Jan's "good" drawing
- The resistior chain is not rotated 16 degrees from
   top - this makes it easier to navigate the "region
   of interest" for studying the high field region.
This page also shows the orientation of the coordinate
system.
The next six pages are pairs of field plots.  Each pair
shows the magnitude of the electric field in a slice
normal to the Z (X, Y) axis.  The slice is taken at
the location of the maximum field.  The second of each
pair of plots is just a zoom in on the hot spot.
The last plot shows that maximum field in an X-slice
vs. X.  If people have questions or suggestions, we
can discuss this in tomorrow's meeting.
 Best regards,
  Dick Majka

 

Electrostatic Calculations for West Support Cone

Calculations from 24-July-2008 with "corrected" resistor chain geometry.

Rusults compared using 1mm mesh and 2mm mesh

FGT Thermo-model D=16cm

Photo documentation of Thermo-model A of FGT, 2009-08-10

FGT Thermo-model D=16cm

Photo documentation of Thermo-model A of FGT, 2009-08-10

Consistent with measurements posted by James on 2009-07-28.

Gas system assembly drawings

 

Please note the following attachments: 

  1. Gas system assembly drawings as of 5 February 2011.
  2. Gas system assembly drawings for cosmic ray tests in clean room at BNL: Safety review on 29 April 2011.
  3. Photo: front of gas system control panel for cosmic ray test - as of 10 May 2011.
  4. Photo: rear of gas system control panel for cosmic ray test - as of 10 May 2011 

Donald Koetke

donald.koetke@valpo.edu

drawings for the FGT full-size prototype frames, HV layer, and GEM foils, August 11, 2008

  These are the current drawings for the FGT full-size prototype frames, HV layer, and GEM foils.  
                                                   Cheers,
                                                           Douglas

 

general routing for the top and bottom GEM, August 16,

 these Gerber files  show the general routing for the top and bottom GEM foil layers plus a representative sample of the GEM foil holes showing the spacing from frame edges and segment boundaries.

 

FGT . . . . . . . . . . A N A L Y S I S

see below

 

Estimation of error of A_L including detector response, May 2008 (Jan)

 This set of analysis was done in preparation to PAC presentation at BNL, May 2008, ( Jan)

study 1 of S/B, A_L, LT=800/pb (Jan)


A_L   on  this has a WRONG sign, I did not know RHICBOS is using different sign convention


Section A



Definitions:

S1,S2 - "signal" yields for 2 spins states (helicity)   "1", "2" , S1+S2=S

B1,B2 - "background" yields for 2 spins states  "1", "2" , B1+B2=B

N1=S1+B1;  N2=S2+B2;  N1+N2=N=S+B - "raw" yields  measured in real experiment

 

Assumptions:

  • background is unpolarized, so   B1=B2=B/2
  • there are 2 independent experiments:
  1. measure spin independent yields for signal counts 's' and  background 'b' counts, yielding the fraction w=b/s, V(w)=w2 *(1/b +1/s) ; (e.g. M-C Pythia simulation using W and QCD events)
  2. measure helicity dependent raw yields N1=S1+B1 and  N2=S2+B2 ; (e.g. theory calculation with specific assumption of AL(W+) , fixed eta & pT ranges, assumed LT & W reco efficiency)  yielding raw spin asymmetry :

 ALraw=(N1-N2)/(N1+N2)= (S1-S2)/(S+B);  V(ALraw)= 4*N1*N2/N3

 I used capital & small letters to distinguish this two experiments.

 

Problem: find statistical error of 'signal' asymmetry:

ALsig= (S1-S2)/S

 

Solution:

  1. ALsig= (1+w) * ALraw 
  2. V(ALsig)= (1+w)2*V(ALraw ) + V(w)*(ALraw)2  where V(x) denotes variance of x, V(N)=N.

 



  Section B - theory



Model predictions of A_L for W+, W- , used files:

 

rb800.w+pola_grsv00_2.root,  rb800.w-pola_grsv00_2.root, rb800.w+unp_ct5m.root       rb800.w-unp_ct5m.root

LT=800/pb, 

Brown oval shows approximate coverage of IST+FGT

Red diamond shows region with max A_L and ... little yield. 

 



Section C - W reco efficiency, fixed ET using fact=1.25



 From Brian, e/h algo ver 2.4, LT=800/pb.

This version uses only tower seed in bin 6-11, this is main reason efficiency is of 40%.

I'll assume in further calculation the W-reco efficiency is of 70%, flat in lepton PT>20 GeV.  

Left: W-yield black=input, green - after cut 15.

Right: ratio. h->Smooth() was used for some histos. 

PT=20.6  sum1=  1223  
PT=25.6  sum1=  1251  sum2= 473 att=1/2.6
PT=30.6  sum1=   987  sum2= 406 att=1/2.4
PT=35.6  sum1=   771  sum2= 343 att=1/2.2
PT=40.6  sum1=   372  sum2= 166 att=1/2.2
PT=45.6  sum1=    74  sum2=  16 att=1/4.6


Section D - QCD reco efficiency,fixed ET using fact=1.25



 From Brian, e/h algo ver 2.4, LT=800/pb. h->Smooth() was used for some histos. 

This version uses only tower seed in bin 6-11 

Left: QCD-yield black=input, green - after cut 15.

Right: ratio= QCD attenuation, not the a;go gets ~3x  'weaker' at PT =[34-37] GeV , exactly where we need it the most

 

PT averaged attenuation of QCD events

PT=20.6  sum1=2122517   
PT=25.6  sum1=528917  sum2=3992 att=1/133
PT=30.6  sum1=135252  sum2= 736 att=1/184
PT=35.6  sum1= 38226  sum2= 320 att=1/120
PT=40.6  sum1= 11292  sum2= 127 att=1/89 
PT=45.6  sum1=  3153  sum2=  41 att=1/77 

 



Section E -  QCD/W  ratio after e/h cuts, algo ver 2.4,fixed ET using fact=1.25



From Brian. h->Smooth() was used for some histos. 

Left: final yield of QCD events (blue) and W-events (green) after e/h algo.

Right: ratio. 

I'll assume w=b/s is better than the red line, a continuous ET dependence:

w(pt=20)=10
w(pt=25)=1.
w(pt=40)=0.5 

 

PT=25.6  sum1=  3992  sum2= 473 att=1/8.4
PT=30.6  sum1=   736  sum2= 406 att=1/1.8
PT=35.6  sum1=   320  sum2= 343 att=1/0.9
PT=40.6  sum1=   127  sum2= 166 att=1/0.8
PT=45.6  sum1=    41  sum2=  16 att=1/2.5
 

 

study 2 , err(AL) , eta=[1,2], LT=800/pb (Jan)

A_L on  this has a WRONG sign, I did not know RHICBOS is using different sign convention, JAN 

 


Section A) Theoretical calculations:

         Assumed LT=800/pb

fpol=new TFile("rb800.w+pola_grsv00_2.root");   <--GRSV-VAL (maximal W polarization)
funp=new TFile("rb800.w+unp_ct5m.root"); 

histo 215

Total W+ yield for lepton ET[20,45] GeV and eta [1,2] is of 7101 for unpolarized cross section and of -2556 for the helicity dependent part.

Assuming 70% beam polarization measured spin dependent asymmetry:

eps_L= P* del/sum= -0.25 +/-0.012

(assuming err(eps)=1/sqrt(sum) )

 Fig 1 , W+ : top row - unpol & pol cross section GRSV-VAL (maximal W polarization),

bottom left: integrated over eta, black=unpol, red=pol

bottom right: asy=P *pol/unpol vs. lepton PT, green=fit


Total W- yield for lepton ET[20,45] GeV and eta [1,2] is of 5574 for unpolarized cross section and of +2588 for the helicity dependent part.

fpol=new TFile("rb800.w-pola_grsv00_2.root"); 
funp=new TFile("rb800.w-unp_ct5m.root"); 

histo 215

Assuming 70% beam polarization measured spin dependent asymmetry:

eps_L= P* del/sum= +0.325 +/-0.013

Fig 2.  W- GRSV-VAL (maximal W polarization)

 



Section  B) Folding in e+,e- reconstruction and QCD background

Assumptions:

  1. LT=800/pb
  2. beam pol P=0.7
  3. e+,e- reco efficiency is 70%, no PT dependence
  4. QCD background to W contamination, after e/h algo no spin dependece
  5. lepton PT range w=backg/signal
    20-25 GeV 5.0 +/- 10%
    25-30 GeV 1.0  +/- 10%
    30-35 GeV 0.8 +/- 10%
    35-40 GeV 0.7 +/- 10%
    40-45 GeV 0.6 +/- 10%

 

Formulas:

  • Theory yields : unpol=sig0(PT) & pol=del(pt) , S1=(sig0+del)/2, S2=(sig0-del)/2
  • Measured yields N1, N2 , for 2 helicity states
    • N1(PT)= eff*[ sig0+del + sig0 * w) /2
    • N2(PT)= eff*[ sig0-del + sig0 * w) /2
    • ALraw(PT)= P* (N1-N2)/ (N1+N2)
    • V(ALraw(PT))= 1/(N1+N2) <-- variance 
    • ALsig(PT)= (1+w(PT))* ALraw(PT) 
    • V(ALsig)= (1+w)2*V(ALraw ) + V(w)*(ALraw)2 
    • dil=1+w
    • QA= |(ALsig)/err(ALsig)| - must be above 3 for meaningful result

Fig 3,  Results for W + GRSV-VAL (maximal W polarization)

 Left : N1(PT)=red, N2(PT) blue. Right: reconstructed signal AL

ipt=0  y-bins=[41,50] unpol=1826.5 pol=-327.3  AL=-0.125 +/- 0.0234   QA=1.8
   B2S=5.0 , N1=3721 N2=3950 ALraw=-0.021 +/- 0.011, dil=6.00  ALsig=-0.125 +/- 0.069

ipt=1  y-bins=[51,60] unpol=1403.0 pol=-265.8  AL=-0.133 +/- 0.0267   QA=2.9
   B2S=1.0 , N1=889 N2=1075 ALraw=-0.066 +/- 0.023, dil=2.00  ALsig=-0.133 +/- 0.046

ipt=2  y-bins=[61,70] unpol=1233.7 pol=-384.7  AL=-0.218 +/- 0.0285   QA=4.7
   B2S=0.8 , N1=643 N2=912 ALraw=-0.121 +/- 0.025, dil=1.80  ALsig=-0.218 +/- 0.047

ipt=3  y-bins=[71,80] unpol=1811.9 pol=-1041.9  AL=-0.403 +/- 0.0235   QA=10.0
   B2S=0.7 , N1=713 N2=1443 ALraw=-0.237 +/- 0.022, dil=1.70  ALsig=-0.403 +/- 0.040

ipt=4  y-bins=[81,90] unpol=808.8 pol=-525.2  AL=-0.455 +/- 0.0352   QA=8.1
   B2S=0.6 , N1=269 N2=637 ALraw=-0.284 +/- 0.033, dil=1.60  ALsig=-0.455 +/- 0.056

sum2=7084.000000 sum3=-2544.850098 asy=-0.251

Fig 4,  Results for W - GRSV-VAL (maximal W polarization)

 

ipt=0  y-bins=[41,50] unpol=1239.1 pol=490.8  AL=0.277 +/- 0.0284   QA=3.2
   B2S=5.0 , N1=2774 N2=2430 ALraw=0.046 +/- 0.014, dil=6.00  ALsig=0.277 +/- 0.086

ipt=1  y-bins=[51,60] unpol=1452.7 pol=641.2  AL=0.309 +/- 0.0262   QA=6.6
   B2S=1.0 , N1=1241 N2=792 ALraw=0.154 +/- 0.022, dil=2.00  ALsig=0.309 +/- 0.047

ipt=2  y-bins=[61,70] unpol=1426.5 pol=689.9  AL=0.339 +/- 0.0265   QA=7.5
   B2S=0.8 , N1=1140 N2=657 ALraw=0.188 +/- 0.024, dil=1.80  ALsig=0.339 +/- 0.045

ipt=3  y-bins=[71,80] unpol=1135.3 pol=596.1  AL=0.368 +/- 0.0297   QA=7.6
   B2S=0.7 , N1=884 N2=467 ALraw=0.216 +/- 0.027, dil=1.70  ALsig=0.368 +/- 0.049

ipt=4  y-bins=[81,90] unpol=313.8 pol=166.4  AL=0.371 +/- 0.0565   QA=4.3
   B2S=0.6 , N1=234 N2=117 ALraw=0.232 +/- 0.053, dil=1.60  ALsig=0.371 +/- 0.086

sum2=5567.280273 sum3=2584.398926 asy=0.325

 

 

 





Another set of results for W+, W- with 2 x worse B/S (the same PT dependence).

Fig 5.  W+ GRSV-VAL (maximal W polarization)

 

Fig 6.  W- GRSV-VAL (maximal W polarization)

 

study 3 , cross check w/ FGT proposal, LT=800/pb (Jan)

 Cross check of my code vs. A_L from FGT proposal

Input from RHICBOS , GRSV-VAL model:

  if(Wsign==1) {             fpol=new TFile("rb800.w+pola_grsv00_2.root");              funp=new TFile("rb800.w+unp_ct5m.root");              WPM="W+ ";     } else {           fpol=new TFile("rb800.w-pola_grsv00_2.root");           funp=new TFile("rb800.w-unp_ct5m.root");             WPM="W- ";     }

 The sign of pol cross section from RHICBOS has reversed convention, I have changed  it to Medison convention.

   hpol->Scale(-1.);

 

Fig 1 W-

from my macro, compare bottom right to blue from fig 2a
 


Fig 2 W-, W+ from FGT proposal


Fig 3 W+,

from my macro, compare bottom right to blue from fig 2b

study 4 , LT=300/pb, eta=+/-[1,2] , W+/- (Jan)

 Calculation of error of A_L for LT=300/pb,   for W± , eta=±[1,2],  PT>20 GeV/c

 

  • Input from RHICBOS , GRSV-STD model:
  • The sign of pol cross section from RHICBOS has reversed convention, I have changed  it to Medison convention.
    hpol->Scale(-1.);
  • beam Pol=70%
  • e+,e- reco efficiency is 70%, no PT dependence
  • QCD background to W signal (B/S) contamination, after e/h algo no spin dependece
      A B C
      ET_range
      (EEMC 3x3_cluster)
      assumed w=backg/signal QCD eve
      suppression needed for(B)
      20-25 GeV  5.0 +/- 20%  - (for W+ or W-)
      25-30 GeV  1.0  +/- 20% 1/539 or 1/520
      30-35 GeV  0.8 +/- 20% 1/196 or 1/169
      35-40 GeV  0.7 +/- 20% 1/43  or 1/ 69
      40-45 GeV  0.6 +/- 20% 1/33 or 1/86
      45-50 GeV  0.5 +/- 20% 1/119 or 1/289
      *) based on full Pythia+GSTAR+BFC simulations of QCD events,
      (study 1 of S/B, A_L, LT=800/pb (Jan) section E)
      after 3x3 EEMC cluster is found
  • eta of the lepton [1,2] (polarized beam is heading toward Endcap)

 

Formulas:

  • Theory yields : unpol=sig0(PT) & pol=delL(pt) , S1=(sig0+delL)/2, S2=(sig0-delL)/2
  • Measured yields N1, N2 , for 2 helicity states
    • N1(PT)= eff*[ sig0 +P*delL + sig0 * w) /2
    • N2(PT)= eff*[ sig0 -P*delL + sig0 * w) /2
    • ALraw(PT)= 1/P (N1-N2)/ (N1+N2)
    • V(ALraw(PT))= 1/P2 1/(N1+N2) <-- variance 
    • ALsig(PT)= (1+w(PT))* ALraw(PT) 
    • V(ALsig)=1/P2 (1+w)2*V(ALraw ) + V(w)*(ALraw)2 
    • dil=1+w
    • QA= |(ALsig)/err(ALsig)| - must be above 3 for meaningful result

Fig 1, W+, eta=[1,2] , ideal detector 


Fig 2, W+, eta=[1,2] , 70% W effi+QCD backg 

 Table 1,  W+ , eta=[1,2] , LT=300/pb

1 2 3 4 5 6 7 8 9 10
reco EMC
ET GeV

 

reco W+ yield
helicity: S1, S2
reco W+  
unpol yield
QCD Pythia
accepted yield
assumed
B/S
reco signal 
AL+err
reco 
AL/err
AL dilution:
1+B/S
QCD yield 
w/ EMC cluster
needed QCD 
suppression *)
20-25 242 ,236 479 2397 5.0 0.019 +/-0.160 0.1 6.00    
25-30 192 ,176 368 368 1.0 0.062 +/-0.105 0.6 2.00 198343 1/539
30-35 190 ,133 323 259 0.8 0.249 +/-0.109 2.3 1.80 50719 1/196
35-40 333 ,141 475 332 0.7 0.576 +/-0.098 5.9 1.70 14334 1/43
40-45 151,61 212 127 0.6 0.606 +/-0.132 4.6 1.60 4234 1/33
45-50 13,6 19 9 0.5 0.457 +/-0.393 1.2 1.50 1182 1/119

    *) after 3x3 EEMC cluster is found, to obtain B/S from column 5



 

Fig 3, W-, eta=[1,2] , ideal detector 


Fig 4, W-, eta=[1,2] , 70% W effi+QCD backg 

Table 2,  W- , eta=[1,2] , LT=300/pb

1 2 3 4 5 6 7 8 9 10
reco EMC 
ET GeV

 

reco W+ yield 
helicity: S1, S2
reco W-  
unpol yield
QCD Pythia
accepted yield
assumed 
B/S
reco signal 
AL+err
reco 
AL/err
AL dilution: 
1+B/S
QCD yield 
w/ EMC cluster
needed QCD 
suppression *)
20-25 116,208 325 1626 5.0 -0.403 +/-0.205 2.0 6.00    
25-30 133,248 381 381 1.0 -0.431 +/-0.112 3.8 2.00 198343 520
30-35 126,247 374 299 0.8 -0.461 +/-0.107 4.3 1.80 50719 169
35-40 97,200 298 208 0.7 -0.495 +/-0.115 4.3 1.70 14334 69
40-45 26,55 82 49 0.6 -0.506 +/-0.203 2.5 1.60 4234 86
45-50 2,5 8 4 0.5 -0.521 +/-0.617 0.8 1.50 1182 293

    *) after 3x3 EEMC cluster is found, to obtain B/S from column 5

 



 

Fig 5, W+, eta=[-2,-1] , ideal detector 


Fig 6, W+, eta=[-2,-1] , 70% W effi+QCD backg 

Table 3,  W+ , eta=[-2,-1] , LT=300/pb

1 2 3 4 5 6 7 8 9 10
reco EMC 
ET GeV

 

reco W+ yield 
helicity: S1, S2
reco W-  
unpol yield
QCD Pythia
accepted yield
assumed 
B/S
reco signal 
AL+err
reco 
AL/err
AL dilution: 
1+B/S
QCD yield 
w/ EMC cluster
needed QCD 
suppression *)
20-25 316,168 484 2424 5.0 0.436 +/-0.175 2.5 6.00    
25-30 235,137 373 373 1.0 0.375 +/-0.111 3.4 2.00 198343 531
30-35 189,132 322 258 0.8 0.252 +/-0.109 2.3 1.80 50719 196
35-40 255,223 479 335 0.7 0.094 +/-0.085 1.1 1.70 14334 43
40-45 109,102 212 127 0.6 0.048 +/-0.124 0.4 1.60 4234 33
45-50 10,9 19 9 0.5 0.027 +/-0.393 0.1 1.50 1182 119

    *) after 3x3 EEMC cluster is found, to obtain B/S from column 5

 

 



 

Fig 7, W-, eta=[-2,-1] , ideal detector 


Fig 8, W-, eta=[-2,-1] , 70% W effi+QCD backg 

Table 3,  W+ , eta=[-2,-1] , LT=300/pb

1 2 3 4 5 6 7 8 9 10
reco EMC 
ET GeV

 

reco W+ yield 
helicity: S1, S2
reco W-  
unpol yield
QCD Pythia
accepted yield
assumed 
B/S
reco signal 
AL+err
reco 
AL/err
AL dilution: 
1+B/S
QCD yield 
w/ EMC cluster
needed QCD 
suppression *)
20-25 157,151 308 1544 5.0 0.024 +/-0.199 0.1 6.00 795943 515
25-30 187,180 367 367 1.0 0.029 +/-0.105 0.3 2.00 198343 540
30-35 187,179 367 293 0.8 0.033 +/-0.100 0.3 1.80 50719 173
35-40 151,144 295 206 0.7 0.033 +/-0.108 0.3 1.70 14334 69
40-45 41,40 81 49 0.6 0.026 +/-0.200 0.1 1.60 4234 86
45-50 3,3 7 3 0.5 0.012 +/-0.624 0.0 1.50 1182 301

    *) after 3x3 EEMC cluster is found, to obtain B/S from column 5

 

study 5 charge sign discrimination


Fig 1 charge reco misidentification (details), M-C simulations

FGT 6 identical disk have active area Rin=11.5 cm, Rout=37.6 cm;
Z location: 70,80,90, 100,110,120 cm with respect to STAR ref frame.

 


Fig 2


 Unpolarized yield for W+, RHICBOS

 


Fig 3


 Unpolarized yield for W-, RHICBOS

 


Fig 4


 Unpolarized & pol yield for W+, RHICBOS, ideal detector

 

Fig 5


 Unpolarized & pol yield for W-, RHICBOS, ideal detector

 

study 6 final plots for PAC, May 2008

A_L   on  this has a  RHICBOS convention to match PHENIX sign choice, opposite to FGT proposal convention.

 

Estimated statistical uncertainty for AL for charge leptons from W decay reconstructed in the Endcap



Fig 1 - Ideal detector



Fig 2 - Realistic detector efficiency & hadronic background, ideal charge reco

 

 

Statistical significance of measured AL vs. zero , integrated over PT, for DSSV2008.
kinematics LT=300/pb LT=100/pb
W+, forward  8.6  5.3
W-, forward   6.7  3.9
W+, backward   5.1  3.0
W-, backward   0.3  0.2

Statistical significance of measured AL vs. zero , integrated over PT, for DRSV-VAL.
kinematics LT=300/pb LT=100/pb
W+, forward  8.6  5.3
W-, forward   8.2  4.7
W+, backward   5.9  3.4
W-, backward   3.9  2.3



Fig 3 - Realistic detector efficiency, hadronic background, and charge reco

 missing

study 7 revised for White Paper, AL(eta), AL(ET) , (Jan)

 Plots show AL for W+, W- as function of ET (fig1) and eta (fig2,3) 

I assumed beam pol=70%, electron/positron reco off 70%, QCD background included, no vertex cut (as for all earlier analysis).

For AL(ET)  I integrated over eta [-2,-1] or [1,2] and assumed the following  B/S(ET) = 5.0 for ET>20 GEV, 1.0 for ET>25, 0.9 for ET>30,.... 

For AL(Eta)  I integrated over ET>25 GeV and assumed a constant in eta & ET B/S=0.8. 


Fig 1. AL(ET). Only Endcap coverage is shown. ( EPS.zip )



Fig 2. AL(Eta) . Only Endcap coverage is shown. ( EPS.zip )



Fig 3. AL(Eta) has continuous eta-axis, binning is exactly the same as in Fig 2.  It includes Endcap & Barrel coverage

(PS.gz) generated by take2/do5.C, doAll21()



 

study 8 no QCD backg AL(eta), AL(ET), also rapidity (Jan)

 Plots show AL for W+, W- as function of ET (fig1,2) and eta (fig3) 

I assumed beam pol=70%, electron/positron reco off 70%, no vertex cut (as for all earlier analysis).

NO QCD background dilution.

For AL(ET)  I integrated over eta [-2,-1] , [-1,+1], or [1,2] and assumed no background

For AL(Eta)  I integrated over ET>25 GeV and assumed no background

 

 


Fig 1 ( PS.zip )


Fig 2 ( PS.zip )

Accounted for 2 beams at mid rapidity.


Fig 3

study 9 sensitivity of STAR at forward & mid rapidity

The goal is to provide overall STAR sensitivity for LT=100/pb & 300/pb.


Common assumptions:

  • beam pol=70%
  • W reco efficiency 70%
  • no losses due to the vertex cut 
  • integrated over ET>20 GeV

 This page is tricky, different assumptions/definitions are used for different eta ranges.

A) Forward rapidity: eta  range [+1,+2],  (shown on fig 1a+b in study 7 revised for White Paper, AL(eta), AL(ET) , (Jan))

determine the degree to which we can measure an asymmetry different from zero.

  • QCD background added, B/S changes with ET.
  • sensitivity  is defined as 3 x stat_error of reco AL 
  • method: fit constant to 'data', use 3x error of the fit
3 sigma(measured AL)
  LT=100/pb LT=300/pb
W+, forward 0.27 0.15
W-, forward 0.30 0.18

 I fit constant to the black points what is equivalent to taking the weighted average.

The value of the average is zero but the std dev of the average tells us sigma(measured AL).
In the table I'm reporting 3 x this sigma.
 
E.g.   for W+ forward we could distinguish on 3 sigma level  between 2 models of AL  if the values of AL differ by at least of 0.27 if we are given LT=100/pb.
 

B) Mid-rapidity: eta  range [-1,+1],  (shown on fig 2a+b in study 8 no QCD backg AL(eta), AL(ET), also rapidity (Jan) )

determine the ratio of  difference of DNS-MIN and DNS-MAX to sigma(measured AL)

  • account for 2x larger yield due to 2 polariazed beams
  • QCD background NOT added
  • sensitivity  is defined as ratio 
  • avr difference of DNS-MIN and DNS-MAX is used
ratio  
   avr(ALMIN-ALMAX) LT=100/pb LT=300/pb
W+, mid 0.15 13 21
W-, mid 0.34 13 22

 

 C) Backward rapidity: eta  range [-2,-1],  (shown on fig 1c+d in study 7 revised for White Paper, AL(eta), AL(ET) , (Jan))

determine the ratio of  difference of DNS-MIN and DNS-MAX to sigma(measured AL)

  • QCD background added, B/S changes with ET.
  • sensitivity  is defined as ratio 
  • avr difference of DNS-MIN and DNS-MAX is used
ratio  
   avr(ALMIN-ALMAX) LT=100/pb LT=300/pb
W+, backward 0.10 1 2
W-, backward 0.5 5 9

 

 

D) Mid-rapidity: eta  range [-1,+1], QCD background added (fig shown below, PS.zip )

determine the ratio of  difference of DNS-MIN and DNS-MAX to sigma(measured AL)

  • account for 2x larger yield due to 2 polariazed beams
  • QCD background added, using B/S(ET) from M-C study at forward rapidity- it is the best what we can do today
  • sensitivity  is defined as ratio 
  • avr difference of DNS-MIN and DNS-MAX is used
ratio  
   avr(ALMIN-ALMAX) LT=100/pb LT=300/pb
W+, mid 0.15 7 11
W-, mid 0.34 10 15

 

 

study 9a sensitivity mid rapidity LT=10/pb

Projection of STAR sensitivity for AL for W+,W-  at mid rapidity for LT=10/pb and pol=60% 

 

Common assumptions:


Fig 1,  no QCD background ( PS.zip )

  Dashed area denotes pt-averaged statistical error of STAR measurement.


Fig 2,   includes QCD background ( PS.zip )

  Dashed area denotes pt-averaged statistical error of STAR measurement.

 

study 9b sensitivity at mid rapidity LT=10/pb Pol=50% or 60%

 Projection of STAR sensitivity for AL for W+,W-  at mid rapidity for LT=10/pb and pol=60% or 50%

Common assumptions:

  • LT=10 pb -1
  • beam pol=60% or 50% 
  • W reco efficiency 70%
  • no losses due to the vertex cut 
  • integrated over eta [-1,+1] 
  • see remaining details in  study 9 sensitivity of STAR at forward & mid rapidity 
  •   
    Estimated significance of STAR measurement
    beam pol  avr AL(W+)THEORY=0.35
    .  avr AL(W-)THEORY=0.15
    sig ALSTAR STAR signifcance   sig ALSTARSTAR signifcane
     50%  0.092  3.8 sigma    0.18  0.8 sigma
     60%  0.077  4.6 sigma    0.15  1 sigma

Fig 1,   Pol=60% ( PS.zip )

  Dashed area denotes pt-averaged statistical error of STAR measurement.

 


Fig 2,   Pol=50% ( PS.zip )

 

e/h algo for Barrel

 not developed, add your analysis as child pages to this page

e/h discrimination in the Endcap

attach different analysis to this child-pages, make them self contained

a) e/h isolation based on Geant Record (Mike, Mar 31)

 For the new QCD background,

partonic pT 15 - 20 GeV : 50,000 events  LT=8.0/pb
partonic pT 20 - 30 GeV : 20,000 events  LT=0.3/b
partonic pT 30 - 50 GeV : 10,000 events  LT=0.4/pb
partonic pT 50+       GeV :   1,000 events  LT=0.8/pb

The high pT tail is still weak.  I could run more high pT events (with the time frame of one more day) or double the bin widths to smooth out the tail and allow for an efficiency plot up to ~50 GeV (albeit with relatively large error bars).  Let me know your choice.

The W files are mit0009 and the QCD files are mit0012.
I use r = 0.26 for the isolation cut, as per the original IUCF proposal, and use the jet finder for the away side veto.

-Mike

 

 

b) e/h isolation based on Geant Record (Mike, April 3)

This is geant-track based analysis

Mike:

Bottom plots are S/B ratios.  

These are extremely loose cuts and I don't think you can base the entire FGT analysis on them.
First of all, the e/p cut isn't quite right.  I use the actual energy of the track whereas most hadrons would just drop MIPs into the calorimeter making the e/p cut very helpful.  I did try to do this in my code but the e/p cut became TOO good and I didn't want to have to deal with trying to convince people of that.
Second of all, no neutral energy isolation cut is made to veto against neutral energy depositions.
Third of all, no shower shape (transverse and longitudinal) information is used at all.
I think it's fair to say that this is a worst case scenario analysis.

Jan: 

I try to understand better this last two S/B plots.
The message from the lower figure is:
* isolation cut alone results with background by a factor 2 to 3 for W+ and factor 4 to 10 for W- with reverse PT dependence for W+ & W-
* away said jet veto helps almost nothing in e/h discrimination.
* if only isolation & away side jet cuts are applied background dominates over signal by a factor of ~300 at PT of 20 GeV and improves to a factor ~2 at PT=40 GeV.

Taken at the face value  Enddcap information add discrimination power of ~1000 for PT=20 GeV  changing toward factor of 6  for PT of 40 GeV/c. (Assuming we want S/B=3)

My comment:
The value of 6 is in reach but value of 1000 may be not trivial.

 e/p cut  - I agree with Mike, 
Looks like the e/p cut applied to h-  reduces it up to a factor of 2  
for pT of 40 GeV.
This cut needs to be dropped for real data- we will not measure PT in  
FGT with reasonable accuracy at large track PT - this reduces overall  
e/h discrimination power for W- at  for PT>30 GeV, so more realistic  
estimate of discrimination power of this (geant based) algo for W- at  
PT of 40 GeV is rather  S/B=0.35 and we need additional factor of 8  
from the endcap.

 

BFC: Filtered Vs. Unfiltered Comparison

Comparison of BFC with and without filtering

 

See pdf file at bottom of page:

The left-hand plots are the unfiltered events and the right-hand plots are the filtered

 

  1. Page 1 shows how many events survive each individual cut. Bins 0 and 1 do not mach because there are different numbers of events in each file and because in my code bin 1 is a cut on 15GeV, not 17GeV where the filtered cutoff was set. All subsequent bins match.
  2. Page 2 shows how many events pass the cuts sequentially. Again, all bins from 2 onward are the same.
  3. Page 3-8 show the trigger patch ET spectrum after sequential cuts were applied, the spectra look the same.
  4. Page 9 shows the ET weighted average eta position of the trigger patch vs the PT weighted average eta position of electrons going into the endcap from the geant record.
  5. Page 10 shows the same information for the phi position.
  6. Page 11 shows the ET of the trigger patch vs the PT of the thrown electrons.

 

Geant Spectra for Filtered and Unfiltered W events

Non-Filtered

Electrons:

Fig1: No eta cuts

 

Fig 2: Eta between -1 and 1

 

Fig 3: Eta between 1.2 and 2.4

 

Positrons:

Fig 4: No eta cuts

 

Fig 5: Eta between -1 and 1

 

Fig 6: Eta between 1.2 and 2.4

 

Filtered on the pythia level: 20GeV in eta [0.8,2.2]

Electrons:

Fig 7: No eta cuts

 

Fig 8: Eta between -1 and 1

 

Fig 9: Eta between 1.2 and 2.4

 

Positrons:

Fig 10: No eta cuts

 

Fig 11: Eta between -1 and 1

 

Fig 12: Eta between 1.2 and 2.4

Pythia analysis version 1.0

Preliminary Analysis of runs in setC2


This analysis was preformed on the events in setC2. See here for details. I ran 48,000 qcd background events and 16000 W events using version 1.0 of my analysis program.

 

Fig 1: Z position of the primary vertex. The W events are on the left and the qcd background events are on the right.


Fig 2: The number of primary tracks found for each event. The W events are on the left and the qcd background events are on the right.


The first cut an event is required to pass is that the transverse energy in a 3X3 patch of towers, centered on the tower with the highest energy, must be greater than 15GeV. All subsequent cuts are made only on events which pass this trigger.


Fig 3: The transverse energy deposited in the trigger patch for each event. The W events are on the left and the qcd background events are on the right.


For this analysis, I used the cuts I developed from looking at single particle events. For the 1-D histograms the W events are in black and the qcd background events are in red. For the 2-D histograms the W events are on the left and the qcd background events are on the right.

  • cutOne: number of hit towers < 11
  • cutTwo: number of hit U strips > 24 and < 42
  • cutThree: not included
  • cutFour: second pre-shower energy > 0.013
  • cutFive: post-shower energy < 0.035
  • cutSix: post-shower over full patch ratio < 0.0007
  • cutSeven: three U strip over all U strip energy > 0.5 and < 0.8
  • cutEight: seven U strip over all U strip energy > 0.65 and < 0.92
  • cutNine: total U plane energy > 0.2
  • cutTen: total U plane energy > 0.3
  • cutEleven: post energy below line running through (0,0) and (0.3,0.05)

 


Fig 4. These plots show how many events passed a particular cut. W events are on the left and qcd background events are on the right. For reference, a total of 5997 W events passed the trigger and 6153 qcd background events passed the trigger.


ver 1.2 : e/h isolation based on TPC tracks (Brian)

Hi everyone,

I have some results for my first iteration of isolation cut and I would
appreciate some feedback as to whether they look reasonable or not.

 These plots were made after requiring that the 3x3 trigger patch ET be greater than 20GeV.


First I find the eta and phi coordinates of the highest tower in the end
cap. I then set a value for the radius. I then loop over all tracks and
towers and if their endcap crossing point lies within my radius I add
their Pt or Et to the total.

 

By highest tower you mean:
- reco vertex is found
- ADC is converted to ET in event reference frame (you are using event-
eta, not detector eta
- you find highest ET tower
I use energy to find the highest tower, not transverse energy.  StEEmcTower highTow = mEEanalysis->hightower(0). And for any event to be processed further, it must have a reco primary vertex found.


By highest tower you mean:
- reco vertex is found
- ADC is converted to ET in event reference frame (you are using event-
eta, not detector eta
- you find highest ET tower
I use energy to find the highest tower, not transverse energy.  StEEmcTower highTow = mEEanalysis->hightower(0). And for any event to be processed further, it must have a reco primary vertex found.
 

StEEmcTower StEEmcA2EMaker::hightower(   Int_t     layer = 0    )
Returns the tower with the largest ADC response

3x3 trigger patch is built around this tower by construction. I ask for the high tower, then I ask for all of its neighbors. The high tower and its neighbors (usually 8, but could be less for high towers on sector boundries) make up the trigger patch.

I then set a value for the radius.I then loop over all tracksDo you mean primary tracks with flag()>0 and nFit/nPos>0.51 ?
Yes, I use these QA conditions.

 

 

These plots show the ratio of the transverse energy in the 3x3 trigger
patch to the total transverse energy in the isolation radius. I ran W
events from files setC2_Weve_N (black curve) and QCD events from files
setC2_qcd_N (red curve).


Trigger ET over Et in iso radius r=0.1:


Trigger ET over ET in iso radius r=0.26:


Trigger ET over ET in iso radius r=0.7:

 

Pythia Analysis ver 2.3: Effects of cuts

Effect of cuts on Trigger Patch ET Spectrum


Here I take a first look at how various cuts effect the trigger patch ET spectrum. For this first run, I look at 13 cuts. The first four reduce the energy range and areas of the endcap that I look in. All of these cuts are applied before any additional cuts are made. The final eleven cuts are various isolation and endcap cuts. For this analysis I used sample ppWprod from setC2 for the W sample and pt30-50 from setC4 for the QCD sampel. Details here. These figures are not scaled to 800inv_pb so all W events must be multiplied by (800/1014) and all QCD events must be multiplied by (800/12.1).


Here are the cuts:

 

  • Cut One: This cut requires that a reconstructed vertex is found, that the vertex lies in the range z=[-70,-50] and that the trigger patch ET be at least 15GeV.
  • Cut Two: This cut requires that the trigger patch ET be at least 20GeV.
  • Cut Three: This cut requires that the ET weighted average eta value of the trigger patch be less than 1.7
  • Cut Four: This cut requires that the highest energy tower be in etabin 6, 7, 8, 9, 10, or 11.
  • Cut Five: This is a cut on the ratio of the trigger patch ET to the transverse energy of all towers within a radius of 0.45 from the hightower. The cut was > 0.96 to pass.
  • Cut Six: This is a cut on the transverse distance between the point where a track crosses the endcap and the position of the high tower. The cut was set at < 0.7 to pass but this was a typo, the correct cut would have been closer to 0.07.
  • Cut Seven: This is a cut on the number of tracks above 1GeV which cross the endcap within a radius of 0.70 of the hightower. There must be 0 or 1 tracks to pass.
  • Cut Eight: This is a cut on the ratio of the energy of the seven highest U strips to the energy of all U strips under the trigger patch. The cut was > 0.7 to pass.
  • Cut Nine: This is a cut on the ratio of the energy of the two highest towers in the trigger patch to the energy of all the towers in the trigger patch. The cut was > 0.9 to pass.
  • Cut Ten: This is a cut on the number of towers with energy greater than 800MeV in the same sector as the trigger patch. The cut was < 6 to pass.
  • Cut Eleven: This is a cut on the number of hit strips in the U plane in the sector containing the trigger patch. The cut was < 48 to pass.
  • Cut Twelve: This is a cut on the ratio of the post-shower energy in the trigger patch to the full energy in the trigger patch. The cut was < 0.0005 to pass.
  • Cut Thirteen: This is a cut on the post-shower energy in the trigger patch. The cut was < 0.04 to pass.


The following plots show the effects the above cuts had on the trigger patch ET spectrum when applied in the order given.

Fig 1: This plot shows the number of events that passed a set of cuts. Bin 1 shows the raw number of events processed and each subsequent bin shows all events that passed a given cut and all cuts before it. So bin eight will show all events that passed cuts 1-7. W events are on the left and QCD events are on the right.


Fig 2: This plot shows the effects of the four phase space cuts on the trigger patch ET spectrum. Again W events are on the left and QCD events are on the right.


Fig 3: This plot shows the effects of the remaining 9 cuts on the trigger patch ET spectrum. Here the black line, instead of representing the raw spectrum, represents the ET spectrum after the four phase space cuts have been applied. Again the cuts are sequential. W events are on the left and QCD events are on the right.


Fig 4: This plot shows the effect of all thirteen cuts in an easier to see form. The black line is the raw spectrum and the red line is the spectrum after the four phase space cuts and the blue line is the spectrum after all remaining cuts. W events on the left and QCD on the right. For the W sample: In the region 20-60, the raw sample contains 4319 events, the sample after the phase space cuts contains 2400 events, and the sample after all cuts contains 1924 cuts. For the QCD sample: In the region 20-60, the raw sample contains 7022 events, the sample after the phase space cuts contains 4581 events, and the sample after all cuts contains 160 events.

 

 

Pythia Analysis ver 2.4: Cuts on all setC4 jobs

Effect of Cuts on Trigger Patch ET

In this analysis I look at the effect the cuts I used in Ver 2.3, as well as two new cuts, have on the transverse energy spectrum of the 3x3 trigger patch. For this analysis I used all files in setC4 for the QCD background and I used setC2_Wprod_N for the W samples. Details here.  I weighted all events to 800 inverse pb. As before the first four cuts restrict the energy range and the area of the endcap we look at and the final eleven cuts are  endcap and isolation cuts. The black curves are the QCD events and the red curves are the W events. All ET and eta's are event eta.

 

Here are the cuts: (Note, ordering different from ver 2.3)

 

  • Cut One: This cut requires that a reconstructed vertex is found, that the vertex lies in the range z=[-70,-50] and that the trigger patch ET be at least 15GeV.
  • Cut Two: This cut requires that the Trigger patch ET be greater than 20GeV.
  • Cut Three: This cut requires that the ET weighted average eta value of the trigger patch be less than 1.7.
  • CutFour: This cut requires that the highest energy tower be in etabin 6, 7, 8, 9, 10, or 11.
  • Cut Five: This is a cut on the ratio of the trigger patch ET to the total ET of all towers within a radius of 0.45 of the high tower. The cut was > 0.96 to pass.
  • Cut Six: This is a cut on the transverse distance between where a track crossed the endcap and the high tower. Counts over all tracks above 1GeV within a radius of 0.70 of the high tower. The Cut was < 0.07 to pass (fixed from Ver 2.3)
  • Cut Seven: (new) This is a cut on the transverse energy found in all towers (barrel and endcap) which lie in a region +/- 0.7 radians from Phi(hightower) + Pi. The cut was < 6.0 to pass.
  • Cut Eight: (new) This is a cut on the transverse distance between where a track crossed the endcap and the high tower. Counts over all tracks above 0.5 GeV within a radius of 0.70 of the high tower. The cut was < 0.07 to pass.
  • Cut Nine: This is a cut on the number of tracks above 1GeV which cross the endcap within a radius of 0.70 of the hightower. There must be 0 or 1 tracks to pass.
  • Cut Ten: This is a cut on the ratio of the energy in the seven highest SMD strips in the U plane under the patch to the energy in all the U strips under the patch. The cut was > 0.7 to pass.
  • Cut Eleven: This is a cut on the ratio of the energy in the two highest towers in the trigger patch to the energy in all the towers of the trigger patch. The cut was > 0.9 to pass.
  • Cut Twelve: This is a cut on the number of towers above 800 MeV in the sector (or sectors) containing the trigger patch. The cut was < 6 to pass.
  • Cut Thirteen: This is a cut on the number of hit strips in the U plane in the sector containing the high tower. The cut was < 48 to pass.
  • Cut Fourteen: This is a cut on the ratio of the post-shower energy in the patch to the full energy in the patch. The cut was < 0.0005 to pass.
  • Cut Fifteen: This is a cut on the post-shower energy in the patch. The cut was < 0.04 to pass.

 

Fig 1: This plot show the effects of all 15 cuts. The black line is the spectrum before any cuts are applied, the red line is the spectrum after the phase space cuts (1-4) are made, and the green line is the spectrum after all 15 cuts have been applied. QCD events are on the left and W events are on the right. For the QCD sample: The raw spectrum contains 718100 events in the region 20-60, the spectrum after the phase space cuts contains 452000 events, and the spectrum after all cuts contains 5215 events. For the W sample: The raw spectrum contains 3476 events in the region 20-60, the spectrum after the phase space cuts contains 1933 events, and the spectrum after all cuts contains 1407 events.

 

 

Fig 2: This plot shows the the QCD spectrum(black) after cuts 1-15 and the W spectrum(red)  after cuts 1-15 on the same figure.

Analysis for Each Pt Range Seperatly(Work in progress)

Results for Each Pt Bin

 

The first plot shows the effects that the first four cuts (the phase space cuts) have on the trigger patch transverse energy spectrum.  The black line is the raw spectrum and the subsequent lines are the cuts, detailed on the parent page.

The second plot shows the effects the remaining cuts have on the ET spectrum. The black line is the spectrum after the phase space cuts, the red line is the spectrum after the isolation cut, the green line is the spectrum after the awayside energy cut and the blue line is the spectrum after all cuts have been applied.

The QCD events are on the left and the W events are on the right. Event ET is used. This is detected ET, not thrown ET. Everything is scaled to 800 inv_pb

Pt 50-inf:

 

Pt 30-50:

 

Pt 20-30:

 

Pt 15-20:

 

Pt 10-15:

Pythia analysis ver 2.3: isolation cuts and EEmc cuts

First Set of Proposed Cuts


The following plots show the cuts I intend to use on my first iteration of the e/h discrimination code. These plots were generated using ppWprod from setC2 (row 11) for W events and mit0015>10 from set C4 (row 13) for QCD events. Details are here. All events in plots have reco vertex in range z=[-70,-50] and have a trigger patch ET > 20GeV. Furthermore the isolation cut plots have the added condition that the high tower does not fall in etabins 1-5 or 12. The W sample is in black and the QCD sample is in red.


Fig 1: Plot of the ratio of transverse energy in the 3x3 trigger patch to transverse energy of towers located inside a radius of 0.45. Cut: > 0.95.


Fig 2: Plot of the displacement between a track and the center of the high tower when there is only one track above 1GeV in a radius of 0.70. Cut: < 0.6.


Fig 3: Plot of the number of hit towers with energy above .8GeV that lie in the same sector as the trigger patch. Cut: < 6.


Fig 4: Plot of the number of hit strips in the U plane in the sector containing the trigger patch. Cut: < 48.


Fig 5: Plot of the energy in the post-shower layers of the 3x3 trigger patch. Cut < 0.04.


Fig 6: Plot of the ratio of energy in the post-shower layers of the 3x3 trigger patch to the total energy in the trigger patch. Cut: < 0.0005. Fig 7: Plot of the ratio of energy in the seven highest U strips under the 3x3 trigger patch to the energy in all the U strips under the trigger patch. Cut: > 0.7.


Fig 8: Plot of the ratio of the energy in the two highest towers in the 3x3 trigger patch to the energy in all towers of the trigger patch.

BFC: 0, 1, and 2 step Filtering Comparison

Comparison Between 0, 1, and 2 Step BFC Filtering

 

For this analysis, I used code V2.5 which is the most recent version to use reconstructed tracks and vertices. I used a scaling factor of 1.25. Event ET used.

 

QCD events

Fig 1: Plot showing how many times each cut is passed individually. Values should coincide after bin 2

Fig 2: Plot showing how many events pass each cut in sequence. Values should coincide after bin 2

Fig 3: Plot showing spectrum after cuts 1-4 have been applied

Fig 4: Plot showing spectrum after cuts 1-5 have been applied

Fig 5: Plot showing spectrum after cuts 1-6 have been applied

Fig 6: Plot showing spectrum after cuts 1-7 have been applied

Fig 7: Plot showing spectrum after cuts 1-8 have been applied

 

W events

Fig 8: Plot showing how many times each cut is passed individually. Values should coincide after bin 2

Fig 9: Plot showing how many events pass each cut in sequence. Values should coincide after bin 2

Fig 10: Plot showing spectrum after cuts 1-4 have been applied

Fig 11: Plot showing spectrum after cuts 1-5 have been applied

Fig 12: Plot showing spectrum after cuts 1-6 have been applied

Fig 13: Plot showing spectrum after cuts 1-7 have been applied

Fig 14: Plot showing spectrum after cuts 1-8 have been applied

 

Investigation of ET scaling factor

ET scaling factor

 

In order to investigate the discrepensy between the thrown pt of a lepton and the ET that the endcap detects, I have run electron events with single energies through the big full chain Jan has used for all the simulations and ploted the detected ET. I ran three energies 20GeV, 30GeV, and 40GeV. I ran 5000 events at each energy and each event has only one electron going into the endcap.

 

Fig. 1: This plot shows the detected ET of the electrons which were thrown at 40GeV.

 

Fig. 2: This plot shows the detected ET of the electrons which were thrown at 30GeV.

 

Fig. 3: This plot shows the detected ET of the electrons which were thrown at 20GeV.

 

We see that multiplying the detected ET by a scale factor of 1.23 recovers the thrown Pt of the electron.

 

Plots for PAC (brian)

Transverse Energy correction factor of 1.23 included

Code Version 2.5

 

 

Fig 1: Isolation cut

Fig 2: Awayside isolation cut

Fig 3: Seven strip cut

Fig 4: Post patch over full patch cut

Fig 5: All cuts spectrum with linear scale for W signal

Fig 6: All cuts spectrum with log scale for W signal

Fig 7: All cuts spectrum showing only W+ linear scale

Fig 8: All cuts spectrum showing only W+ log scale

Fig 9: All cuts spectrum showing only W- linear scale

Fig 10: All cuts spectrum showing only W- log scale

 

Brief explanation of cuts found here.

 

 

Below are plots showing the contributions that other W decay channels will have to the spectrum. All spectrum are weighted to 800inv_pb. Details can be found in rows 14-18 of the plot detailing events in setC2 here.

 

Fig 11. Spectrum of W decay events.

Fig 12. Spectrum of Z production events.

Fig 13. Spectrum of W jet events.

Fig 14. Spectrum of Z jet events.

Fig 15 Spectrum of W Z events.

 

Fig 16: Table of integrated yields for W, Z processes scaled to 800 inv_pb after all cuts have been applied.

 

  PT>20 PT>25
W_Prod 1827 1359
W_Dec 64 30
Z_Prod 113 67
W_Jet 212 144
Z_Jet 18 8
WZ 4 2

 Fig 17a,b: Table of Pythia cross section and branching ratio 

 

Fig 18: Table of integrated QCD yields for all pT bins scaled to 800 inv_pb after all cuts have been applied.

 

  pT>20 pT>25
All pT 16460 4892
pT50-inf 67 54
pT30-50 2247 1430
pT20-30 9179 2611
pT15-20 3628 558
pT10-15 1032 86
pT05-10 308 154

 

Pythia Analysis Summary

Analysis Summary

 

Introduction

A future goal of the STAR collaboration is the measurment of flavor separated polarized anti-quark distribution functions. To make these measurments we will be looking at charged leptons - electrons and positrons - arising from the decay of W bosons created in quark anti-quark collisions. One difficulty in making this measurment is the large flux of background hadronic particles, giving a signal to background on the order of 1/1000. The following details my efforts at developing an algorithm which can reject the hadronic background while retaining the signal leptons to achieve a S/B of greater than one-to-one over a significant portion of the observed lepton transverse energy spectrum which runs from roughly 20-50GeV.

 

Basic Philosophy

Discrimination between leptons and hadrons is posible because of the different processes giving rise to signal and background events as well as different showering properties of leptons and hadrons in the EEMC. Hadronic events tend to be dijets, meaning these events will deposit two blobs of energy located 180 degrees away in azimuth from eachother. Leptonic events, on the other hand, arise from the decay of W bosons which produce a charged lepton and a neutrino. The neutrino is not detected so only one blob of energy is deposited in the detector. This difference allows for the application of an away-side cut which will veto events having significant energy 180 degrees away from the candidate lepton. Hadrons and leptons also behave differently inside of the EEMC with hadrons tending to produce larger and wider showers as compared to leptons due to collisions with nuclei. This difference in shower behavior means isolation cuts on the energy around a candidate lepton can be effective. Finally, the EEMC is roughly 21 electron radiation lengths deep and only one hadron radiation length deep meaning that much more hadronic energy will escape the back of the detector, allowing for cuts based on the amount of energy leaving the detector. Below are pictures from starsim showing the evolution of hadronic and leptonic showers in the EEMC:

Fig 1: Picture of a 30GeV charged pion going into the EEMC generated using starsim.

 

Fig 2: Picture of a 30GeV electron going into the EEMC generated using starsim.

 

 

As described above, the algorithm discriminates between leptons and hadrons in three basic ways: looking at the number of tracks and energy around candidate leptons, vetoing events with too many tracks or too much energy 180 degrees away in azimuth from the candidate lepton, and by comparing shower evolution in the EEMC. Another important aspect of the discrimination algorithm is the trigger patch. The trigger patch is always taken to consist of the tower with the highest energy - which is also taken as the position of the candidate electron - and all adjacent towers, usually yielding a 3x3 patch. This trigger patch is the area of the EEMC where shower evolution is investigated. The investigation of shower evolution is possible in the EEMC due to the five separate readout layers: the two pre-shower layers, the two shower maximum detectors (SMDs) and the post-shower layer. The pre-shower layers are located at the front of the detector where few leptons will have started to shower, the SMDs are located five out of 24 layers deep and are positioned at the depth where there is maximum shower energy deposition, and the post-shower layer is at the back of the detector where most lepton showers will have died out. By looking at the energy deposited in the separate layers, one can get an idea of the longitudinal shower development inside the EEMC. One can also see the transverse shower development by looking at the number of hit strips in the SMD layers. Many combinations of EEMC quantites were tried over the course of developing the discrimination algorithm, but the best discrimination by far was achieved by looking at the ratio of the energies in the seven highest adjacent SMD strips under the trigger patch to the energy of all SMD strips under the trigger patch. Less effective but still usefull EEMC cuts include the ratio of the energy in the two trigger patch towers with the highest energy to the energy in the full trigger patch and the ratio of the energy in the post-shower layer to the energy in the full trigger patch. The away-side and isolation cuts provide powerful discrimination as well and are largly independent of the EEMC cuts listed above.

 

Code Versions

The discrimination code has gone through many versions as new cuts were tested, tracking methods were improved, and other improvements were made. Below is a brief discription of each version as well as the source code for future reference.

 

V1.0:

Version 1.0 is the first version of the discrimination code designed to work with the Pythia simulations run at MIT. This version borrowed heavily from earlier code designed to work on single thrown lepton and hadron events. The code used to access the EEMC information was taken directly from this earlier work. In addition to the EEMC anlysis this version includes code to access tracking information from the MuDst files as well as a function to determine if a track passed close to the tower with highest energy. Also included was a primative function which looked at the awayside energy only in the endcap. This code looked at approximately eleven different cuts and displayed what the trigger patch transverse energy spectrum would look like after each one was applied as well as what the spectrum would look like when several different combinations of cuts were applied.

  • Original source code can be viewed here
  • Page detailing analysis using this code can be viewed here

 

V1.1:

Version 1.1 follows the same basic pattern as version 1.0 detailed above. The major difference is in the trigger criteria used to determine wether an event should be analysed. In version 1.0, all events needed to have a trigger patch ET greater than 15GeV in order to be processed further. In addition to the 15GeV condition, version 1.1 requires that all events have a found vertex and that that vertex be found in within ten centimeters of z=-60. (The simulations were generated with the interaction point at -60 cm so that tracks with large etas would pass through more TPC volume). The next significant change was the inclusion of a function which calculated the transverse energy deposited in a tower taking into accout the z position of the vertex as ET value for a particle originating at z=-60 can be significantly different from the ET value gotten assuming the particle originated at z=0. Minor changes include the addition of a function which allows the setting of the energy threshold needed to consider a tower hit, a function which gives the ET weighted position of the trigger patch, and the investigation of several new cut quantities.

  • Original source code can be viewed here

 

V2.0:

Version 2.0 differs from the 1.x versions in that it implements functions allowing isolation cuts, both same side and away side, utilizing tower energies, track momenta, and barrel information. Simulations done by Les Bland showed that these kinds of cuts had the potential to provide nearly two orders of magnitude in background reduction. These functions add up the transverse energy/momentum of all towers/tracks which fall within a user set region. For the same side isolation cut, this region is a circle with user set radius centered on the high tower. For the away side isolation cut, the region is a slice in phi with a user set width around the line which is 180 degrees away in azimuth from the high tower. In addition to the isolation cut functions, this version addopts the new cuts from version 1.1 and adds histograms exploring various radii for the isolation cuts. The code to calculate the transverse energy was also changed again, this time to set the 'center' plane of the tower to the position of the SMD plane as opposed to the actual physical center because we expect the most shower activity at the SMD depth.

  • Original source code can be viewed here

 

V2.1:

Version 2.1 is very similar to version 2.0 and contains only minor changes. One concern with previous versions was that events occuring at high eta did not have reconstructed tracks because of poor TPC tracking in this region and thus it was hard to get a good idea of how well cuts using tracking were doing. To investigate this problem, several isolation cuts and histograms were made with the condition that the hightower not be located in etabins 1-5 - which excluded high eta events - or etabins 11&12(because of edge effects around the transition from endcap to barrel). In addition to this bin restriction investigation, new histograms were made to study the effects of moving the trigger patch ET threshold from 15 to 20GeV on the cut quantites from version 2.0. Other small changes included the addition of a crude function to determine approximately how many electrons/positrons were going into the endcap and a modification to the away side isolation function to read out the track, barrel, and endcap energies separately.

  • Original source code can be viewed here

 

V2.2:

Version 2.2 adds two functions which provide a different way to carry out the same side isolation cuts. The first function counts the number of tracks above a certain threshold which cross the endcap within some radius of the high tower and also calculates the transverse displacement between the track and the high tower if there is one and only one track in the radius. This one and only one track scheme is flawed and is modified in later versions. The second function calculates the transverse energy deposited in the barrel and endcap towers within a certain radius. The idea behind the new isolation cuts was that QCD events should have many tracks around the high tower while W decay events should have few, maybe only one. It was also thought that events with one and only one track in the isolation radius may only be displaced some slight amount from the high tower and that this could give good lepton hadron discrimination. There are many new histograms exploring these ideas.

  • Original source code can be viewed here

 

V2.3:

Version 2.3 makes many changes to how the cuts are organized. The trigger patch ET spectrum is shown after each individual cut as well as after each cut in succession. The cuts in this version were chosen from the cuts in the previous version which showed the best discrimination power, all other cuts were removed. In addition to re-organizing the cuts, new trigger conditions were included. Along with the trigger conditions from previous versions, events now must have a trigger patch ET greater than 20GeV, have the high tower be in etabins 6-11, and have the ET weighted trigger patch eta position be greater than 1.7 to be processed further.

  • Original source code can be viewed here
  • Page detailing analysis using this code can be viewed here

 

V2.4:

Version 2.4 is very similar to version 2.3 in terms of cuts. Cuts on the away side energy and the displacement between tracks and the high tower have been added. This version of the code has also been cleaned up significantly, with many extraneous histograms and function calls being removed. This version also allowed for overall weighting of the event samples being processed. This allows for the scaling of all pythia samples to the same integrated luminosity. This method of weighting the samples was cumbersome because the code must be recompiled for each seperate simulation batch and if a mistake were made, the whole pythia sample would need to be rerun. In the future, this method is dropped in favor of a script which weights the batches while merging the seperate event files.

  • Original source code can be viewed here
  • Page detailing analysis using this code can be viewed here

 

V2.5:

Version 2.5 is the last version of the code to use cuts based on reconstructed tracks from the TPC. It is also the version used to produce plots for several presentations and proposals. As such, it has many histograms which were specifically requested for those presentations, chief among them histograms showing the effects of cuts on the trigger patch ET spectra for electrons and positrons separately. In anticipation of using GEANT tracking in future versions a function was created which would count tracks going into a isolation region using the GEANT record. This function looped over all vertices within three centimeters of the primary vertex and counted all the tracks above a certain threshold which made it into the isolation region. This method often double-counts tracks and is modified in later versions. In addition to the new functions and histograms, two glitches in the code have been fixed in this version. The first is the addition of an ET scaling factor which single particle simulations had shown were needed to make the thrown electron pt and detector response agree, the value used is 1.23. The second correction fixed a problem in calculating the phi displacement between two objects in the endcap. Because the endcap coordinate system splits the detector into two halves and maps one 0 -> 180 and the other 0 -> -180, just taking the difference between phi coordinates will occasionaly lead to the wrong actual displacement. To rectify this, the difference in phi is now calculated as acos(cos(phi1 - phi2)) instead of just (phi1 - phi2). In this version the cuts remain the same as in version 2.4.

  • Original source code can be viewed here

 

V3.0:

Version 3.0 uses GEANT for tracking and vertex finding information. Looking at the results from previous code, it was thought that tracking efficency and vertex finding were still too poor. It was decided to use GEANT tracking in anticipation of the improved tracking which would be available with the FGT upgrade. With the perfect tracking from GEANT, it was possible to explore the upper limit of how much discrimination track cuts could provide. Because of the perfect tracking, the volume of the detector looked at would not need to be restricted as much. Thus, the trigger conditions were changed from version 2.5 to eliminate the restriction that the ET weighted eta position of the trigger patch must be less than 1.7. The restriction on the etabin of the high tower was also relaxed so that it could be located in bins 2-11 (bins 1 and 12 were still excluded to reduce edge effects). The isolation cuts are now handled by four functions, two calculate the energy deposited in the calorimeters for the same side and away side cuts, and two count the number of tracks above a certain pt threshold going into the same side and away side regions. The track counting functions still have the double counting problem in this version. The last major change to this code is the way in which the cuts are organized and displayed. In this version the cuts are divided into three groups, the initial trigger cuts that all events must pass, the isolation cuts and the EEMC cuts. Each cut quantity is displayed after the trigger cuts as usual, but now each cut is displayed after the trigger cut and the isolation cuts have been applied and each cut is displayed again after all other cuts have been applied so that in the end, each cut is displayed three separate times. This was done to see which cuts where independent of each other.

  • Original source code can be viewed here
  • Page detailing analysis using this code can be viewed here

 

V3.1:

Version 3.1 of the code solves the double counting problem that the previous track counting functions had. In this version the track counting is done recursively. The GEANT track and vertex infromation is set up as a network of connected nodes. Each node is a vertex and represents a particle decay and the lines coming out of each node represent the resultant particles of this decay. These lines will then connect to other nodes if that particle decays. The track counting function loops through all the particle lines coming from the primary vertex and asks where the next vertex connected to that line is, if there is no other vertex or the vertex is located greater than three centimeters away from the primary vertex, the particle is considered stable and is counted (if it is heading into the proper region). If the next vertex is less than three centimeters from the primary vertex however, the function is called again and loops over the tracks coming from this secondary vertex and the process is repeated until all tracks have been looped over. In this way, the code avoids counting the track of a particle which decays along with the tracks of its daughter particles. In addition to the double counting problem the values of the cuts were changed in this version. Version 3.0 threw away too many signal events so version 3.1 used the same set of cuts but just loosened the values where the cuts were made so they did not throw away as many events.

  • Original source code can be viewed here
  • Page detailing analysis using this code can be viewed here

 

V3.2:

Version 3.2 is very similar to version 3.1, the major differences are the values used for the cuts. The quantities cut on are the same as in version 3.0 and 3.1, but now the values have been tightened slightly compared with version 3.1, so now each cut throws away around 2 or 3% of the signal. In addition to this tightening, the away side energy and track quantities were plotted against the trigger patch ET in a 2-D plot. This allowed for cuts which rejected much more background at low pt than was possible before with the same 1-D cuts.

  • Original source code can be viewed here
  • Page detailing analysis using this code can be viewed here

 

V3.21:

Version 3.21 is almost exactly the same as version 3.2, the major difference is that this version introduces an ineffiecency into two of the track cuts. The cuts on the number of charged tracks above .5 and 5GeV going into the same side isolation circle both have large numbers of events with zero tracks in the QCD background sample and very few events with zero tracks in the signal sample. It is likely that many of these neutral tracks are Pi0's. With GEANT tracking, these Pi0's can be identified with 100% efficiency, but for real data, material in front of the detector will cause many of the Pi0's to convert giving rise to charged tracks. This conversion process will make the zero charged track cuts less efficient. To explore the effects of these conversions, a random number generator was used to pass 30% of events with zero charged tracks in both cuts. The only other change from version 3.2 was to move the 2-D histograms showing the trigger patch ET vs the cut quantites after all other cuts but themselves were applied so that they would be incremented properly.

  • Original source code can be viewed here
  • Page detailing analysis using this code can be viewed here

 

Results

Detailed results from the latest version of the discrimination code can be found on the pages linked to in sections 3.2 and 3.21 but the major points as well as some summary plots will be shown here.

 

Fig 3: This plot shows the final trigger patch ET spectra after all cuts have been applied. The QCD background is in black and the W signal is in red. The plot on the left is from v3.2 and the plot on the right is from v3.21.

 

Fig 4: This plot shows the signal-to-background ratio for versions 3.2 and 3.21 after all cuts have been applied.

 

Fig 5: This table shows the effectivness of each cut for version 3.2. 

Cut QCD Events Cut Signal Events Cut
Iso Cut 235 of 754: 31% 18 of 1151: 2%
Small Iso Track 82 of 536: 15% 11 of 1131: 1%
Away ET Cut 1300 of 1754: 74% 9 of 1135: 1%
Away Track Cut 924 of 1378: 67% 45 of 1165: 4%
Big Iso Track 3542 of 3997: 89% 4 of 1124: <1%
2 Highest Towers 63 of 521: 12% 21 of 1141: 2%
7 U Strips 527 of 1195: 44% 31 of 1175: 3%
7 V Strips 579 of 1195: 48% 33 of 1175: 3%
Hit U Strips 7 of 468: 1% 10 of 1138: <1%
Hit V Strips 8 of 468: 2% 10 of 1138: <1%
PS patch/Full patch 151 of 606: 25% 10 of 1130: <1%

 

Fig 6: This table shows the effectivness of each cut for version 3.21. 

Cut QCD Events Cut Signal Events Cut
Iso Cut 739 of 2852: 26% 17 of 1107: 2%
Small Iso Track 1042 of 2931: 36% 11 of 1089: 1%
Away ET Cut 3983 of 5897: 68% 15 of 1093: 1%
Away Track Cut 3461 of 4897: 71% 63 fo 1121: 6%
Big Iso Track 3310 of 5171: 64% 4 of 1080: <1%
2 Highest Towers 110 of 2024: 5% 19 of 1097: 2%
7 U Strips 1194 of 3620: 33% 30 of 1131: 3%
7 V Strips 1323 of 3620: 37% 32 of 1131: 3%
Hit U Strips 27 of 1966: 1% 10 of 1096: 1%
Hit V Strips 44 of 1966: 2% 10 of 1096: 1%
PS patch/Full patch 189 of 2095: 9% 10 of 1088: 1%

 

Figures 5 and 6 show the effect of each cut after all other cuts have been applied. (The exception is for cuts on U and V plane quantites, in which case all other cuts but the similar cut on the other plane are applied). For each cut, the number of events which survived the other cuts and the number of those events which the cut removes are shown. So for example, looking at the iso cut in figure three, 754 background events survive the thirteen other cuts and the iso cut removes 235 of these surviving events. This can be taken as a way to measure how independent a cut is from all the others. The tables show that with perfect tracking, the cut on the number of charged tracks above 5GeV is by far the best cut, but with the 30% ineffieciency added in the effectiveness of this cut is reduced so that it is around parity with the away side cuts.

 

Conclusions

As the figures above show, the discrimination code achieves a signal-to-background ratio of greater than one-to-one over a significant portion of the lepton transverse energy range, indicating that background should not be an insurmountable barrier to preforming the W analysis at STAR. These results were obtained using GEANT and any analysis of real data will need to monitor vertex finding and tracking efficency to ensure they do not degrade the effectiveness of the cuts too much. The addition of the FGT should help with these issues and it is likely that the code will need to be optimized to take advantage of the improved tracking of the FGT. Finally, this analysis is based on a powerful discrimination code which can be refined and modified to suit future analyses.

 

 

 

 

Pythia Analysis ver 3.0: Analysis of set C4 events using geant record

Analysis of all setC4 events using geant tracks and vertices

 

In this analysis, I looked at all QCD background events from setC4 as well as W events from setC2 Wprod detailed here. I used version 3.0 of my analysis code which uses geant vertices and tracks instead of reconstructed vertices and tracks as version 2.5 did. I have also made changes to the quantities I make cuts on, see below. All transverse energy is event ET and an energy scaling factor of 1.23 is used.

 

Cuts:

I make 14 cuts described below. Plots of the cut spectra can be found here. Pages 1-11 show the cut spectra after 3 preliminary phase space cuts have been made (spectra of the first 3 cuts are not shown). Every event must pass the first three cuts to be considered. Pages 12-18 show cut spectra 8-14 after cuts 1-7 have been applied. Pages 19-29 show cut spectra after all cuts but its own have been applied. Pages 30-32 show a possible alternative cut.

  1. Cut 1: Require that the geant vertex be in the region [-70,-50]
  2. Cut 2: Require that the trigger patch ET > 20GeV
  3. Cut 3: Require that the high tower not be in eta bin 1 or 12
  4. Cut 4: Isolation cut - Ratio of the ET in the trigger patch to the ET in an iso cone with r=0.45. Require > 0.96 to pass
  5. Cut 5: Track iso cut - Number of geant charged tracks with pT>0.5GeV in an iso cone with r=0.7. Require < 3 to pass
  6. Cut 6: Awayside isolation cut - ET in a region Pi +/- 0.7 radians from the high tower in phi. Require < 6.0 to pass
  7. Cut 7: Awayside track cut - Number of geant charged tracks with pT>0.5GeV in same region as cut 6. Require < 7 to pass
  8. Cut 8: Track near high tower - Number of geant charged tracks with pT>5.0GeV in an iso cone with r=0.7. Require < 2 to pass
  9. Cut 9: Ratio of energy in two highest towers in trigger patch to energy in all towers in trigger patch. Require > 0.9 to pass
  10. Cut 10: Ratio of energy in 7 highest adjacent U strips under the patch to the energy in all U strips under the patch. Require > 0.7 to pass
  11. Cut 11: Ratio of energy in 7 highest adjacent V strips under the patch to the energy in all V strips under the patch. Require > 0.7 to pass
  12. Cut 12: Number of hit U strips in sector containing the trigger patch. Require < 48 to pass
  13. Cut 13: Number of hit V strips in sector containing the trigger patch. Require < 48 to pass
  14. Cut 14: Ratio of energy in patch post-shower layer to full energy in patch. Require < 0.0005 to pass

 

I have also made several 2-D plots of other quantities which may provide good electron/hadron discrimination. These plots can be found here.

  1. Page 1 is a plot of the trigger patch energy Vs. the post shower energy
  2. Page 2 is a plot of the energy in both the U and V strips under the trigger patch Vs. the energy in all post shower layers in the trigger patch
  3. Page 3 is a plot of the energy in both the U and V strips under the trigger patch Vs. the energy in all 2nd pre-shower layers in the trigger patch
  4. Page 4 is a plot of the trigger patch energy Vs. the energy in all 2nd pre-shower layers in the trigger patch

 

Spectra

The plots showing the effect of the various cuts on the trigger patch ET spectrum can be found here. Pages 1-14 show the effect that the first 3 cuts plus the individual cut has on the trigger patch ET spectrum. So, for example, page 7 shows the spectrum after cuts 1, 2, 3, and 7. Pages 15-26 shows the effects that a number of cuts applied sequenitally has on the spectrum. In all plots the black curve is the detected ET spectrum before any cuts have been made and the red curve is the ET spectrum after the cuts in question have been applied.

 

Fig 1: This plot shows the effects of all the cuts applied in sequence on the trigger patch ET spectrum

 

Fig 2: This plot shows the final trigger patch ET spectra after all cuts have been applied. The QCD background is in black and the W signal is in red.

 

Pythia Analysis ver 3.1: Analysis of set C5 events using geant record

Analysis of all setC5 events using geant tracks and vertices

 

In this analysis I looked at all QCD background events from setC5, which has an integrated luminosity on the order of what we expect to get in data. I also looked at W events from setC2 Wprod. The details of both event samples can be found here. This analysis was done using version 3.1 of my code which uses geant vertices and tracks, meaning we have perfect tracking for the cuts. All transverse energy is event ET and an energy scaling factor of 1.23 is used. All samples are scaled to LT=800 inverse pb.

 

Cuts:

I make 14 cuts which are described below. These cuts have been loosened compared to those in version 3.0, now each cut throws away no more that 1% of the signal. I have also added conditions to cuts 5 and 8 to reject events where no charged track was found. Plots of the cut spectra can be found here. Pages 1-11 show the cut spectra after the 3 preliminary phase space cuts have been made (spectra of the first 3 cuts are not shown). All events must pass the first three cuts to be analysed further. Pages 12-18 show cut spectra 8-14 after cuts 1-7 have been applied to them. Pages 19-29 show all the cut spectra after all cuts but their own have been applied.

  1. Cut 1: Require that the geant vertex be in the region [-70,-50]
  2. Cut 2: Require that the trigger patch ET>20GeV
  3. Cut 3: Require that the high tower not be in eta bin 1 or 12
  4. Cut 4: Isolation cut - Ration of the ET in the trigger patch to the ET in an iso cone with r=0.45. Require > 0.94 to pass
  5. Cut 5: Track iso cut - Number of geant charged tracks with pT>0.5GeV in an iso cone with r=0.7. Require < 5 and > 0 to pass
  6. Cut 6: Awayside isolation cut - ET in a region Pi +/- 0.7 radians from the high tower in phi. Require < 9.0 to pass
  7. Cut 7: Awayside track cut - Number of geant charged tracks with pT>0.5GeV in same region as cut 6. Require < 10.0 to pass
  8. Cut 8: Track near high tower - Number of geant charged tracks with pT>5.0GeV in an iso cone with r=0.7. Require there be 1 and only 1 track to pass
  9. Cut 9: Ratio of energy in two highest towers in trigger patch to energy in all towers in trigger patch. Require > 0.75 to pass
  10. Cut 10: Ratio of energy in 7 highest adjacent U strips under the patch to the energy in all U strips under the patch. Require > 0.45 to pass
  11. Cut 11: Ratio of energy in 7 highest adjacent V strips under the patch to the energy in all V strips under the patch. Require > 0.45 to pass
  12. Cut 12: Number of hit U strips in sector containing the trigger patch. Require < 52 to pass
  13. Cut 13: Number of hit V strips in sector containing the trigger patch. Require < 54 to pass
  14. Cut 14: Ratio of energy in patch post-shower layer to full energy in patch. Require < 0.002 to pass

 I have also made several 2-D plots of other quantities which my provide good electron/hadron discrimination. These plots can be found here.

  • Page 1 is a plot of the iso radius (r=0.7) ET Vs. the trigger patch ET
  • Page 2 is a plot of the away side ET Vs. the trigger patch ET
  • Page 3 is a plot of the trigger patch ET Vs. the number of charged tracks above 0.5GeV in the away side region
  • Page 4-6 show the same plots as pages 1-3 after cuts 1-7 have been applied
  • Page 7-9 show the same plots as pages 1-3 after all cuts have been applied
  • Page 10 is a plot of the trigger patch energy Vs. the post shower energy
  • Page 11 is a plot of the energy in both the U and V strips under the trigger patch Vs. the energy in all post shower layers under the trigger patch
  • Page 12 is a plot of the energy in both the U and V strips under the trigger patch Vs. the energy in all 2nd pre-shower layers in the trigger patch
  • Page 13 is a plot of the trigger patch energy Vs. the energy in all 2nd pre-shower layers in the trigger patch
  • Page 14-17 show the same plots as pages 10-13 after cuts 1-7 have been applied
  • Page 18-21 show the same plots as pages 10-13 after all cuts have been applied

 

Spectra

The plots showing the effect of the various cuts on the trigger patch ET spectrum can be found here. Pages 1-14 show the effect that the first 3 cuts plus the individual cut has on the trigger patch ET spectrum. So, for example, page 7 shows the spectrum after cuts 1, 2, 3, and 7. Pages 15-26 show the effects that a number of cuts applied sequentially has on the spectrum. In all plots the black curve is the detected ET spectrum before any cuts have been made and the red curve is the ET spectrum after the cuts in question have been applied.

 

Fig 1: This plot shows the effects of all the cuts applied in sequence on the trigger patch ET spectrum. For the QCD sample: The raw spectrum contains 2.6E6 events in the region 20-70, the spectrum after the phase space cuts (1-3) contains 2.2E6 events, and the spectrum after all cuts contains 1.5E4 events. For the W sample: The raw spectrum contains 4645 events in the region 20-70, the spectrum after the phase space cuts contains 3747 events and the spectrum after all cuts contains 3378 events.

 

Fig 2: This plot shows the final trigger patch ET spectra after all cuts have been applied. The QCD background is in black and the W signal is in red.

 

 

Pythia Analysis ver 3.21: Analysis of set C5 events using geant record

Analysis of all setC5 events using Geant tracks and vertices

 

In this analysis I attempt to get a feeling for the effects that imperfect tracking will have on the trigger patch ET spectrum while still using geant tracking information. My main focus was on the inefficencies which will arise in trying to identify converting Pi0's, so I focused on cuts 5 and 8. Both of these cuts have large numbers of events with no charged tracks and it is likely that many of these events are Pi0's. In v3.2 of the analysis code cuts 5 and 8 both throw away events with no charged tracks, so to simulate the tracking inefficency I use a random number generator to allow 30% of events with zero charged tracks to pass each cut. The code I used for this analysis is v3.21 which uses the same cuts as v3.2 except for the code introducing the 30% inefficency. Descriptions of the cuts used as well as explanations of the plots in the pdf files can be found on the page describing v3.2 of my code found here. I have also changed the 2-D plots of the trigger patch ET Vs. the cut quantities found on pages 23-33 of the 2-D plot pdf. They now show the plots after all cuts but themselves have been applied as opposed to v3.2 where they were shown after all cuts were applied.

 

Fig 1: These plots show the effects of all the cuts applied in sequence on the trigger patch ET spectrum. The top plot is from v3.2 and the bottom plot is from v3.21. The number of events cut for v3.2 can be found on the main page for that analysis. The numbers for v3.21 are given here. For the QCD sample: The raw spectrum contains 9.9E5 events in the region 20-70, the spectrum after the phase space cuts (1-3) contains 8.2E5 events, and the spectrum after all cuts contains 1906 events. For the W sample: The raw spectrum contains 1671 events in the region 20-70, the spectrum after the phase space cuts contains 1347 events and the spectrum after all cuts contains 1078 events.

 

Fig 2: This plot shows the final trigger patch ET spectra after all cuts have been applied. The QCD background is in black and the W signal is in red. The plot on the left is from v3.2 and the plot on the right is from v3.21.

 

 

 

 

Pythia Analysis ver 3.2: Analysis of set C5 events using geant record

Analysis of all setC5 events using Geant tracks and vertices

 

In this analysis I looked at all QCD background events from setC5, which has an integrated luminosity on the order of what we expect to see in the data. I alo looked at W events from setC2 Wprod. The details of both event samples can be found here. This analysis was done using version 3.2 of my code which uses geant vertices and tracks, meaning we have perfec tracking for the cuts. All transverse energy is event ET and an energy scaling factor of 1.23 is used. All samples are scaled to LT=300 inverse pbnote that the samples in all previous versions were scaled to 800 inverse pb.

 

Cuts:

I make 14 cuts which are described below. These cuts have been tightened slightly compared to those in version 3.1, now each cut throws away between 2-3% of the signal, except for cuts 6 and 7. For cuts 6 and 7, I have used a 2-D plot of the patch ET Vs. the cut quantity to cut harder on the low pT background. I have also included plots of quantites which we thought had potential to be used as cuts.

 

Plots of the 1-D spectra can be found here. Pages 1-11 show the cut spectra after the 3 preliminary phase space cuts have been made (spectra of the first 3 cuts are not shown). All events must pass the first three cuts to be analysed further. Pages 12-18 show cut spectra 8-14 after cuts 1-7 have been applied to them. Pages 19-29 show all the cut spectra after all cuts but their own have been applied. Pages 30 and 31 contain plots showing the ratio of U(V) strips above 0.5MeV under the trigger patch to the total number of U(V) strips under the patch. Pages 32 and 33 contain plots showing the number of U(V) strips above 0.5MeV in the sector(s) containing the trigger patch. Pages 34-37 contain the last four plots with cuts 1-7 applied and pages 38-41 contain the last four plots with all cuts applied.

 

Plots of the 2-D spectra can be found here. Pages 1-33 show the trigger patch ET Vs. the cut quantites so we can fine tune the cuts to eliminate background in particular ET ranges. Pages 1-11 show the cut spectra after the 3 phase space cuts have been made. Pages 12-22 show the cut spectra after cuts 1-7 have been applied. Pages 23-33 show the cut spectra after all cuts have  been applied. Pages 34 and 35 show the trigger patch Energy Vs. the ratio of energy in the 7 highest adjacent U(V) strips under the trigger patch to all U(V) strips under the trigger patch. Page 36 shows the trigger patch Energy Vs. the ratio of pre-shower energy in the trigger patch to all energy in the trigger patch. Pages 37-39 show the last three quantities with cuts 1-7 applied and pages 40-42 show the same quantities with all cuts applied. Pages 43 and 44 show trigger patch ET Vs. the ratio of U(V) strips above 0.5MeV under the trigger patch to the total number of U(V) strips under the patch. Pages 45 and 46 show the trigger patch ET Vs. the number of U(V) strips above 0.5MeV in the sector(s) containing the trigger patch. Pages 47-50 show the last four plots with cuts 1-7 applied and pages 51-54 show the plots with all cuts applied. Page 55 is a plot of the trigger patch energy Vs. the post shower energy. Page 56 is a plot of the energy in both the U and V strips under the trigger patch Vs. the energy in all post shower layers under the trigger patch. Page 57 is a plot of the energy in both the U and V strips under the trigger patch Vs. the energy in all 2nd pre-shower layers in the trigger patch. Page 58 is a plot of the trigger patch energy Vs. the energy in all 2nd pre-shower layer in the trigger patch. Pages 59-62 show the last four plots after cuts 1-7 have been applied and pages 63-66 show the same plots after all cuts have been applied.

 

  1. Cut 1: Require that the geant vertex be in the range [-70,-50]
  2. Cut 2: Require that the trigger patch ET>20GeV
  3. Cut 3: Require that the high tower not be in eta bin 1 or 12
  4. Cut 4: Isolation cut - Ratio of the ET in the trigger patch to the ET in an iso cone with r=0.45. Require > 0.96 to pass (1-D cut)
  5. Cut 5: Track iso cut - Number of geant charged tracks with pT>0.5GeV in an iso cone with r=0.7. Require < 4 and > 0 to pass (1-D cut)
  6. Cut 6: Awayside isolation cut - ET in a region Pi +/- 0.7 radians from the high tower in phi. (2-D cut)
  7. Cut 7: Awayside track cut - Number of geant charged tracks with pT>0.5GeV in same region as cut 6. (2-D cut)
  8. Cut 8: Track near high tower - Number of geant charged tracks with pT>5.0GeV in an iso cone with r=0.7. Require there be 1 and only 1 track to pass (1-D cut)
  9. Cut 9: Ratio of energy in two highest towers in trigger patch to energy in all towers in trigger patch. Require > 0.83 to pass (1-D cut)
  10. Cut 10: Ratio of energy in 7 highest adjacent U strips under the patch to the energy in all U strips under the patch. Require > 0.6 to pass (1-D cut)
  11. Cut 11: Ratio of energy in 7 highest adjacent V strips under the patch to the energy in all V strips under the patch. Require > 0.6 to pass (1-D cut)
  12. Cut 12: Number of hit U strips in sector containing the trigger patch. Require < 52 to pass (1-D cut)
  13. Cut 13: Number of hit V strips in sector containing the trigger patch. Require < 52 to pass (1-D cut)
  14. Cut 14: Ratio of energy in patch post-shower layer ot full energy in patch. Require < 0.001 to pass (1-D cut)

 

Specta

The plots showing the effect of the various cuts on the trigger patch ET spectrum can be hound here. Pages 1-14 show the effect that the first 3 cuts plus the individual cut has on the trigger patch ET spectrum. So, for example, page 7 shows the spectrum after cuts 1, 2, 3, and 7. Pages 15-26 show the effects that a number of cuts applied sequentially has on the spectrum. In all plots the black curve is the detected ET spectrum before any cuts have been made and the red curve is the ET spectrum after the cuts in question have been applied.

 

Fig 1: This plot shows the effects of all the cuts applied in sequence on the trigger patch ET spectrum. For the QCD sample: The raw spectrum contains 9.9E5 events in the region 20-70, the spectrum after the phase space cuts (1-3) contains 8.2E5 events, and the spectrum after all cuts contains 455 events. For the W sample: The raw spectrum contains 1742 events in the region 20-70, the spectrum after the phase space cuts contains 1405 events and the spectrum after all cuts contains 1120 events.

 

 

Fig 2: This plot shows the final trigger patch ET spectra after all cuts have been applied. The QCD background is in black and the W signal is in red.

 

FGT . . . . . . . . . . C A L I B R A T I O N


  1. Algorithm for calibration
  2. status tables for year 2010

 


 

Beam Test at DESY, May 2011

Planning the Beamtest at DESY

 

 

 

 

Important Dates:

 Scheduled from May 16-30

 

Contacts:

 

general:

Anselm Vossen (avossen@indiana.edu)

 

DESY testbeam page:

http://adweb.desy.de/~testbeam/

People that are going

 

 

Equipment that has to be shipped

Equipment/People/Shipping
 

Equipment

Qty Size Weight  ? Contact Person/Institution Shipping Details (from where to where) When?

Comments (e.g. shipping details

safety aspects)

   FGT Quadrants          MIT      
   Det Fixture          MIT      
   positioning/alignment          MIT      
   gas-setup          Valpo/MIT      might be available at DESY - see below
   bottled gas (premixed?)          DESY      
   FEE board 6        MIT      
   terminator board          MIT      
   interconnector board          MIT      
   cable and patch          MIT      
  signal cables         IU/UKY      
  power cables         IU/UKY      
  RG-59 HV cables 3       DESY?      
  readout crate 1 2.5'x 4'x 3.5x 100 lbs   ANL      
  ARC 1 1'x 1'x 0.3' 4 lb   ANL      
  ARM 3 1'x1'x0.3' 4 lb   IU      
  HVPS 1 1'x1'x0.3' 8 lb   IU      
  computer incl. DRORC 1 1'x3'x4' 73 lb   DESY?      
  Nim logic         DESY      
  data fiber 1       IU      
  hand tools and scope         DESY      
  diff probe 1       IU      
  Sys clock source                already provided by ARC
  Misc computer equipment (PC etc)                

 

Gas at Desy

 

The DESY gas group can supply premixed gas. We have to ask well in advance.

Flowmeters etc. should also be available. We have to bring tools

 

 Test Beam Description

 

can be found here:

 

adweb.desy.de/home/testbeam/WWW/Description.html

 

 

Safety at DESY

 

Inspection List for equipment

 

General:

adweb.desy.de/~testbeam/documents/AllgemeineSicherheitsunterweisungD5englisch.pdf

Radiation protection

adweb.desy.de/~testbeam/documents/RadiationProtectionInstructionsTestBeam-NM-1-2006.pdf

Testbeam safety briefing:

adweb.desy.de/~testbeam/documents/SafetyBriefingTestBeam.pdf

We have to assign one person responsible for radiation safety

That person is:

 

 

 

 Travel Infos for Hamburg/Germany

Fly into Hamburg

Today the price from JFK is ~$950 roundtrip

 

Within Germany, rail is good idea if you book in advance

www.bahn.de/i/view/USA/en/index.shtml

ask me if you want to look for special fares ( I saw that that site is in German)

 

HOUSING

DESY hostel:

guest-services.desy.de/hostel_in_hamburg/hostels_info/

 

I haven't been at DESY, so if somebody else has a better idea, please tell me

 

CHECKLIST

 

 OPEN ISSUES

Gas

 

Planned Measurements

Planned Measurements

 

For each of these measurements we should have a plan/protocoll what we want to do (conditions, time, software...)

 

  • Normal
    0

    false
    false
    false

    EN-US
    X-NONE
    X-NONE

    /* Style Definitions */
    table.MsoNormalTable
    {mso-style-name:"Table Normal";
    mso-tstyle-rowband-size:0;
    mso-tstyle-colband-size:0;
    mso-style-noshow:yes;
    mso-style-priority:99;
    mso-style-parent:"";
    mso-padding-alt:0in 5.4pt 0in 5.4pt;
    mso-para-margin:0in;
    mso-para-margin-bottom:.0001pt;
    mso-pagination:widow-orphan;
    font-size:11.0pt;
    font-family:"Calibri","sans-serif";
    mso-ascii-font-family:Calibri;
    mso-ascii-theme-font:minor-latin;
    mso-hansi-font-family:Calibri;
    mso-hansi-theme-font:minor-latin;
    mso-bidi-font-family:"Times New Roman";
    mso-bidi-theme-font:minor-bidi;}

    Reproduction of test beam results at FNAL:  drupal.star.bnl.gov/STAR/blog/surrow/2011/feb/02/fgt-testbeam-fnal-prototype-triple-gem-detectors

  • Cluster reconstruction, Cluster size,
  • R-Phi Correlations
  • Efficiency
  • Cluster amplitude
  • HV scans
  • Residuals
  • Dependence on

    Normal
    0

    false
    false
    false

    EN-US
    X-NONE
    X-NONE

    /* Style Definitions */
    table.MsoNormalTable
    {mso-style-name:"Table Normal";
    mso-tstyle-rowband-size:0;
    mso-tstyle-colband-size:0;
    mso-style-noshow:yes;
    mso-style-priority:99;
    mso-style-parent:"";
    mso-padding-alt:0in 5.4pt 0in 5.4pt;
    mso-para-margin:0in;
    mso-para-margin-bottom:.0001pt;
    mso-pagination:widow-orphan;
    font-size:11.0pt;
    font-family:"Calibri","sans-serif";
    mso-ascii-font-family:Calibri;
    mso-ascii-theme-font:minor-latin;
    mso-hansi-font-family:Calibri;
    mso-hansi-theme-font:minor-latin;
    mso-bidi-font-family:"Times New Roman";
    mso-bidi-theme-font:minor-bidi;}

    on inclination angle for P/Phi reconstruction

  • Noise (i.e. electronics noise of the readout). RMS of pedestals calibrated to MIP. Optimum parameters for APV in FGT. (Parameters will affect gain as well as noise, of course.) Necessity (or hopefully not) of tracking pedestals by capid.
  •  Number of timebins to use in readout, and algorithm to get pulse amplitude/time from the timebin data. Uniformity of signal shape over the detector.
  • Crosstalk

  • Normal
    0

    false
    false
    false

    EN-US
    X-NONE
    X-NONE

    /* Style Definitions */
    table.MsoNormalTable
    {mso-style-name:"Table Normal";
    mso-tstyle-rowband-size:0;
    mso-tstyle-colband-size:0;
    mso-style-noshow:yes;
    mso-style-priority:99;
    mso-style-parent:"";
    mso-padding-alt:0in 5.4pt 0in 5.4pt;
    mso-para-margin:0in;
    mso-para-margin-bottom:.0001pt;
    mso-pagination:widow-orphan;
    font-size:11.0pt;
    font-family:"Calibri","sans-serif";
    mso-ascii-font-family:Calibri;
    mso-ascii-theme-font:minor-latin;
    mso-hansi-font-family:Calibri;
    mso-hansi-theme-font:minor-latin;
    mso-bidi-font-family:"Times New Roman";
    mso-bidi-theme-font:minor-bidi;}

    Rate dependence (trigger rate and signal rate).

  • Normal
    0

    false
    false
    false

    EN-US
    X-NONE
    X-NONE

    /* Style Definitions */
    table.MsoNormalTable
    {mso-style-name:"Table Normal";
    mso-tstyle-rowband-size:0;
    mso-tstyle-colband-size:0;
    mso-style-noshow:yes;
    mso-style-priority:99;
    mso-style-parent:"";
    mso-padding-alt:0in 5.4pt 0in 5.4pt;
    mso-para-margin:0in;
    mso-para-margin-bottom:.0001pt;
    mso-pagination:widow-orphan;
    font-size:11.0pt;
    font-family:"Calibri","sans-serif";
    mso-ascii-font-family:Calibri;
    mso-ascii-theme-font:minor-latin;
    mso-hansi-font-family:Calibri;
    mso-hansi-theme-font:minor-latin;
    mso-bidi-font-family:"Times New Roman";
    mso-bidi-theme-font:minor-bidi;}

    .Radiation effects on the frontend electronics

  • Normal
    0

    false
    false
    false

    EN-US
    X-NONE
    X-NONE

    /* Style Definitions */
    table.MsoNormalTable
    {mso-style-name:"Table Normal";
    mso-tstyle-rowband-size:0;
    mso-tstyle-colband-size:0;
    mso-style-noshow:yes;
    mso-style-priority:99;
    mso-style-parent:"";
    mso-padding-alt:0in 5.4pt 0in 5.4pt;
    mso-para-margin:0in;
    mso-para-margin-bottom:.0001pt;
    mso-pagination:widow-orphan;
    font-size:11.0pt;
    font-family:"Calibri","sans-serif";
    mso-ascii-font-family:Calibri;
    mso-ascii-theme-font:minor-latin;
    mso-hansi-font-family:Calibri;
    mso-hansi-theme-font:minor-latin;
    mso-bidi-font-family:"Times New Roman";
    mso-bidi-theme-font:minor-bidi;}

     EMI issues. (For the most part if there are any, have to be

     addressed first and independently of the rest of the testing, test

    beam or otherwise.)

  • Normal
    0

    false
    false
    false

    EN-US
    X-NONE
    X-NONE

    /* Style Definitions */
    table.MsoNormalTable
    {mso-style-name:"Table Normal";
    mso-tstyle-rowband-size:0;
    mso-tstyle-colband-size:0;
    mso-style-noshow:yes;
    mso-style-priority:99;
    mso-style-parent:"";
    mso-padding-alt:0in 5.4pt 0in 5.4pt;
    mso-para-margin:0in;
    mso-para-margin-bottom:.0001pt;
    mso-pagination:widow-orphan;
    font-size:11.0pt;
    font-family:"Calibri","sans-serif";
    mso-ascii-font-family:Calibri;
    mso-ascii-theme-font:minor-latin;
    mso-hansi-font-family:Calibri;
    mso-hansi-theme-font:minor-latin;
    mso-bidi-font-family:"Times New Roman";
    mso-bidi-theme-font:minor-bidi;}

    Optimum gain setting for the FGT in consideration of the limited dynamic range of APV. What tail of large events can we afford to cut off and still make the position resolution? Conversely how much noise is affordable and still make the position resolution. Presumably get to a plot of resolution as a function of HV setting.

  • Normal
    0

    false
    false
    false

    EN-US
    X-NONE
    X-NONE

    /* Style Definitions */
    table.MsoNormalTable
    {mso-style-name:"Table Normal";
    mso-tstyle-rowband-size:0;
    mso-tstyle-colband-size:0;
    mso-style-noshow:yes;
    mso-style-priority:99;
    mso-style-parent:"";
    mso-padding-alt:0in 5.4pt 0in 5.4pt;
    mso-para-margin:0in;
    mso-para-margin-bottom:.0001pt;
    mso-pagination:widow-orphan;
    font-size:11.0pt;
    font-family:"Calibri","sans-serif";
    mso-ascii-font-family:Calibri;
    mso-ascii-theme-font:minor-latin;
    mso-hansi-font-family:Calibri;
    mso-hansi-theme-font:minor-latin;
    mso-bidi-font-family:"Times New Roman";
    mso-bidi-theme-font:minor-bidi;}

    Survival of FEE to breakdown/discharges in detector

FGT . . . . . . . . . . D O C U M E N T S

  1. Proposal (December 2007)
  2. Project documentation on deltag5  at MIT server
  3. Tree-structure of FGT web page (graph)
  4. Conclusions of Reviews
    date place format occasion
    January 2008 MIT pdf STAR Forward GEM Tracker Review Committee
  5. NIM paper from the 2007 FermiLab beam test of GEM disks is available on ArXiv http://arxiv.org/abs/0808.3477

OTHER DOCUMENTS

  1. RHIC long range plan as of December 2006 (out link)
  2. RHIC PAC, May 2008, STAR BUR
  3. STAR Detector West Side PicturesClick Here (deltag5 @MIT)
  4. Frank's Thesis 

 

Documents/Minutes of prelimnary safety review, Sept. 09

Files from the prelimnary safety review at BNL Sept 09

FGT . . . . . . . . . . DAQ

 DAQ related information for FGT

 

APV Readout System Long Cable Test Setup

The APV front-end ASIC which forms the core of the Forward GEM Tracker readout system combines a sensitive preamplifier, switched-capacitor analog memory array, and low-voltage differential analog output buffer.

Operating such an ASIC directly over a long cable, with the analog output digitized at the far end of the cable, potentially presents some challenges. Of course, there are are also opportunities, to minimize the power dissipation inside the inner field cage region, minimize dead materials, and to maximize reliability by placing most of the electronics in an easily serviceable location on the STAR electronics platform.

At IUCF we are constructing a pair of test boards, one which models the APV readout module "ARM", the other which models the APV cable connector board.

Besides testing the performance of the MIT APV motherboards with a long cable interface, this set of test boards is important to:

  • Develop the interface definitions between the IUCF "ARM" and the MIT "APV Motherboard"
  • Demonstrate a low-dropout low-voltage regulator for the APV power, and characterize its performance
  • Demonstrate the control of APV chips and an I2C temperature sensor via the UART - I2C bridge chip
  • Evaluate the effects of various thermal and grounding options for the FGT
  • Run the APV's for detector testing (either with an external ADC and clock source, or with the connector board here and the full ARM to be developed

Here are the design files:

The connector board should be compatible with a pair of FGT APV Motherboards, a total of 10 APV chips. The mock readout board provides only two channels of analog line receiver, testing two different concepts for this. One is a DC coupled line receiver using Analog Devices # AD8129, the other is a transformer-coupled line receiver using a TI # OPA684 opamp. The transformer solution should have superior noise and common-mode rejection and lower power, but it is of course not DC coupled as we would wish. It could be used if DC restoration is applied digitally in the FPGA (on the real ARM).

First results:

Here is the APV readout sequence, looking good:

 

The "noise" which is apparent here is merely crosstalk from the clock signal, and as such will be easily removed by the filter in front of the ADC. Neither that filter nor the cable frequency equalization filter is in place for the measurement above.

Clock frequency was 40 MHz; APV was triggered at 1 kHz from a pulse generator. No inputs connected, no shield box. Cable is Belden 1424A, 110 feet, coiled up on workbench.

ARM - FEE Final Interface Prototype

Details of final prototype of FEE interface circuitry for FGT APV Readout Module "ARM". This includes the isolated remote-regulated power supplies, the isolated I2C line interface, the isolated LVDS clock & trigger line drivers, and the differential analog receiver. Cable connectors and pinouts here are proposed for final application. (In actual ARM, cables interface through a rear transition board in the crate through the 96-pin DIN connector to ARM module. This is not implemented here - cables connect directly using same connector type and pinouts on the cables.)

 

Here are the details:

Brief overview of FGT FEE/Readout electronics chain

This is a short overview of the front end and readout electronics of the FGT. The emphasis is on providing some documentation on all the components. At present most of the items exist only as prototypes, I will try to keep this page current as things get finalized.

First, the front end board, which has 5 APV chips. Two front end boards are used per FGT quadrant (24 quadrants total). One sits at each end of the quadrant. As four quadrants fit together to form an FGT disk, the pairs of front end boards from adjacent quadrants physically sit close to each other. They are serviced by a common cable, interconnect board, and terminator board (to be described shortly).

Below is a picture of the first FGT quadrant (actually just a mechanical test assembly, the pad plane is an old design and is defective). Apologies this is a shiny object photographed on a shiny table in the Bates cleanroom. What you see here is mainly the aluminized mylar gas window which is also the ground plane, sits a couple of mm above the pad plane. On each end of the quadrant is a row of five Samtec MEC6 card-edge connectors (0.635 mm contact pitch): four 140 pin connectors and one 80 pin in the center of the other four. This connects the 640 = 5 APV * (128 ch/APV) signals from the pad plane to the FEE board. The ground is carried separately (see description below). The constraints on FGT inner and outer radius do not permit assigning any of these connector contacts to grounds.

 

Below is a picture of a front end board installed on an FGT quadrant. This is a view from "outside" i.e. this is the side of the front end board that does not have the APV chips. Actually in this picture is a mechanical mockup board, but is mechanically identical to the final design. The white RTV which can be seen in this picture is covering the edge of this quadrant assembly.

 

And here is the actual front end board. In this and the picture above you can see the two ground contact points which will be fastened with screws and washers to wide contact strips extending from the ground foil. This provides the connection of APV signal ground. The ground foil is also similarly connected to the bypass capacitor feeding bias voltage to the bottom of the last GEM foil (connections not detailed here).

Note that it is the back side of this board that would be seen in the quadrant picture above. The two front end boards serviced as a pair have the APV chips mounted on the outward facing sides. Similarly the ground foil connections are made on this outward facing side. From the quadrant's perspective, the chip side of the APV board faces in toward the center of the quadrant.

The front-end board is serviced by the "interconnect board" on one end and a "terminator board" on the other. All interface lines run through from end to end so that the design is symmetrical. Half of the frontend boards have the terminator on the right in this picture, half have the interconnect board on the right. There is only a single flavor of front end board.

The schematic of the front end board is (here). It consist only of five APV chips and a minimal set of support components.

The APV chip is a 128-channel preamp / shaper / SCA / readout mux chip developed for CMS tracker silicon, and also subsequently deployed for GEM readout in COMPASS. Most of the operational details are described in the user guide and in presentations available on the CMS tracker web pages. The APV chip incorporates an analog FIR filter (what the user guide refers to as deconvolution mode) for tail cancellation / pileup reduction at the expense of higher noise. We don't intend to make use of it. It should be noted that the appropriateness of the (fixed) filter coefficients is of course dependent on the sample clock rate. Which is another reason we don't intend to use it.

The APV chip sample clock can be run at least as fast as 40 MHz (as in CMS). For RHIC, we prefer to lock to a multiple of our collision frequency so that the signals can be synchronously sampled avoiding any additional complications or errors from asynchronous sampling. We will use 4x RHIC strobe, 37.532 MHz, a reasonable match to the capability of the APV chip.

The APV chip readout clock can be the sample clock or 1/2 the sample clock rate. With 1/2 the sample clock a single-point readout requires 280/37.532 MHz = 7.46 us. This is amply fast in comparison with other STAR detectors even if multi-point readout is employed. So we will use only the 1/2 rate readout because it significantly eases the signal transport problem.

[Insert here description of the interconnect board / terminator board. (voltage reg, clk/trig receiver, temp sensors, POR circuit, terminations)]

The above comprises the front end electronics subsystem. The interfaces from the front end electronics to the readout electronics are, in total:

  1. Power supplied at +/-1.8 V with remote sense of +1.8, ground, and -1.8 at the terminals of the front end electronics (interconnect board). The power supply is in the readout electronics, and is isolated from ground.
  2. SCL/VSS pair and SDA/VSS pair that connect to the APV chips and other devices, e.g. temperature sensors, on the front end electronics. This I2C interface runs with 2.5 V logic and complies with the I2C standard except in regard to line capacitance limitations where special considerations are taken. The pull-up current source is in the readout electronics. The I2C master in the readout electronics is isolated from ground.
  3. CLK+/- low voltage differential logic signal (continuously running). Source is isolated from ground (transformer coupled) in the readout electronics. The line is terminated at the front end electronics and at the readout board (double-termination).
  4. TRIG+/- low voltage differential logic signal. Source is isolated from ground (transformer coupled) in the readout electronics. The line is double terminated.
  5. 10x (in case of FGT) or up to 12x (in case of IST) analog signal output lines each from one APV chip. All are double terminated and are received at the readout board with a high common-mode impedance line receiver.

(more description/documentation of the readout system to come...)

Event size estimation

 Estimation of FGT event size for pp events @ 500 GeV is 20KB/eve after ZS, physics event will use 80% of this volume.

  1. empty event: 3.7KB Concluding: for 3-sample empty events we need 3.7 KB   300*(2+2+2+2)+30000*(2+2+2+2)/200+100=3700 bytes.
    • total # of channels: 128 ch X 10 APV x4 quad x 6 disks = 30K channels.
    • zero suppression (ZS) is  aiming to keep 1/100 of ADC channels, set to about 3 sigma above ped. Needs testing with data & real electronics, time stability, beam halo, AC-noise . Perhaps we can ZS more.
    • with ZS we need 4 bytes per hit:
      • we need 2 bytes (log2(30k)=14.9) for channel ID
      • ADC value needs up to 12 bits, assume we write it as 16 with 4 bits unused, as with ESMD
    • we may want to keep ADC for 3 time slots per event (using 25 ns integration window) increasing hit size to 8=4+2+2 bytes.
    • it is enough to keep 1/1000 events w/o ZS for monitoring of pedestals
    • event header needs 100 bytes
  2.  

  3. pp data taking
    • assume every track fires 5 strips (will be more at Rin and less at Rout due to varied width of phi strips)
    • trigger event is always embedded in 6 minBias pileup events 
      • at top RHIC luminosity we have 1.5 minB interactions per bXing
      • 300 nsec of analog pulse --> need to account for 4 pre-trigger bXings --> 4x1.5=6 minB eve/trig eve 
      • based on OLD Pythia simulations (obsolete disk size & location) @ 500 GeV one expects 1 track per quadrant per minB event.
    • conclusion: 1440 ADCs will fire due to underlying pileup event   (4 tracks * 6 disks * 2 planes *6 events *5 strips= 1440 

       

    • W-trigger will fire mostly on jets, ASSUME HT consumes lot of jet energy and there is 10 charged (low pT) tracks in such jet. 10 tracks * 6 disks * 2 planes * 5 strips= 600 ADCs
    • total physics event content will be 2000 ADC channels. This requires 16KB (2000 *8 bytes)
  4.  

  5.  Heavy Ion even - no study was performed so far.

 

FGT DAQ drawings and hardware documentation

These are the official drawings and documentation used for fabrication of the FGT "DAQ" hardware. We will try to maintain this page up-to-date with any revisions.

APV Readout Controller (ARC)

  • Pictures
  • Schematic (pdf)
  • Schematic (format=?)
  • BOM
  • Layout (format=?)
  • Board fabrication data
  • Assembly data

APV Readout Module (ARM)

ARM Back-of-Crate Board (ABC)

  • Pictures
  • Schematic (pdf)
  • Schematic (Altium)
  • BOM
  • Layout (Altium)
  • Fabrication data files

FGT FEE Patch Panel

  • Pictures
  • Schematic (pdf)
  • Schematic (..)
  • BOM
  • Layout (..)
  • Fabrication data files

Other documentation

FGT . . . . . . . . . . M E E T I N G S

 TIME is going backwards.

2009-05-21 , RHIC user meeting @ BNL

2009-05-12 , quarterly review presentation of the FGT project

2009-03-23, RCS presentation, Bernd 

2009-08-08, 3rd quarterly review at BNL,Bernd

 

FGT-HN Upload site  (StarTube) : You do not have access to view this node  ,   Instruction for new users uploading FGT documents  


Weekly FGT phone meetings (minutes by Doug Hasell or Gerard)

2009

June 19,  26

2008

February: 1, 8, 15, 22, 29

March: 7, 14, 21, 28

April 11 : Brian e/h-algo , Dave: X/X0 in Endcap

May 2 ,


 IEEE in Dresden, 2008, Frank's talk about FGT


FGT meeting at BNL, September 2008 GT meeting at BNL 


September 2008, Local seminar at MIT by Jan

Title: The STAR Forward GEM Tracker, Talk (PDF),  abstract


2nd STAR IFC integration meeting, BNL, July 23, 2008 

Star Integration meeting


Forward Tracking Extension Meeting at MIT, June, 2008

Agenda


STAR Collaboration Meeting, Davis, June, 2008


STAR IFC integration meeting, BNL, May 16, 2008


BNL PAC, May 8, 2008, 


 IEEE NSS 2008 in Dresden, Germany, May 2008,

Franks abstract ,


 FGT meeting at IUCF on April 24-25  on April 24-26, 2008


RSC meeting on April 21, 2008 , all talks ,  DG, W, ppTrans


DIS2008, London April 2008, web-page, some talks: ppTrans RHIC program (PPT) Jan


FGT review at MIT, January 7-8, 2008 ( detailed agenda )

  •  Monday, January 7, 2008: MIT-LNS, 13:00-18:00 , Talks (tmp link to MIT)
  •  Tuesday, January 8, 2008: MIT-Bates, 09:00-17:00 Talks (tmp link to MIT)

 

Cosmic Stand Safety Review April 29th 2011 at BNL

Date: Friday April 29, 2001
> Time: 1:30 pm
> Place: C-AD LCR

overview cosmic teststand: Anselm

FGT disks (internal HV distribution etc) : Ben/Jason
electronics/cables/etc. : Gerard
Gas system (short) : Don

FGT. . . . . . . . . . H A R D W A R E -- E L E C T R O N I C S

 

 

01 2D_GEM Sensor Board for test at FANL / Miro

In this document one can find schematic topology and architecture of 2D_GEM Sensor Board which was used for test at FANL.

02 2D_GEMCU for Test in FANL / Miro

In this document one can find complete schematic topology and block diagrams for 2D_GEM Readout Control Unit which was used in test run at FANL.

03 APV Module for Test 2D_GEM at FANL / Miro

In this document one can find complete schematic topology and hardware architecture for APV Module which was used for test of 2D_GEM at FANL.

04 APV Motherboard Design / Miro

Document "APV Motherboard Design" for FGT April's meeting at IUCF on April 24, 2008.

05 APV_MODULE for STAR/FGT READOUT

APV_MODULE is PCB where on top of APV_BOARD is bond with epoxy glue SIG_BOARD

06 BNL 26Sep@008 Meeting

FEE Design

07 Document for Charge Sharing 2D_Readout module / Miro

In this document one can find GERBER files for Charge Sharing 2D_Readout module. This module will be used for test and study charge sharing effect in GEM detectors. All other components for assembling of this charge sharing setup we will use from old GEM detectors which we used for test purposes at FANL last year.

NOTE: Files in "TSTBOARD.zip" are possible open with P-CAD2004 software tool and file "tstboard.pdf" is "pdf" accessible file where one can see architecture of mentioned unit.

07 Document for GEM/FANL prototype / Miro

This document was requested by Dave Underwood and Gerrard Visser for they purposes to compare they design with GEM/FANL prototype buildup at MIT/Bates Linear Accelerator. 

08 Module for FGT Mechanical Test / Miro

In attached document is multipurpose module with which one can test all mechanical and connectivity features.

09 VHDL Programs and State Machines for GEM/FANL / Miro

In this document one can find VHDL Programs and State Machines for 2D_GEM Control Unit which was engaged in readout process from GEM detector at FANL.

10 WSC and the GEM quarter section frames (Jason)

 drawings showing the final dimensions of the WSC and the GEM quarter section frames,

8-19-2009, Jason Bessuille

Front End Electronics Drawings and Hardware Documentation

These are the official drawings and documentation used for fabrication of the FGT Front End Electronics hardware. We will try to maintain this page up-to-date with any revisions.

To view design files, download the Altium Viewer (no cost).

FGT Readout Module (FRM)

Terminator Board

Interconnect Board

High Voltage Board

FGT. . . . . . . . . . H A R D W A R E -- S L O W C O N T R O L S

 Documentation of FGT Slow Controls Subsystem

(add child pages with specific documents below)

 

The manufacture's calibration for these flow meters is shown here.  It is nonlinear as you can see. So, going from ~40 mm to >65 mm more than doubles the flow rate: it is well over 100 cc/min.

Scale reading Flow Rate
  (mm)                     (cc/min)
----------------------   --------------
    65                         104.0
    60                           91.5
    55                           79.5
    50                           69.0
    45                           59.2
    40                           49.5
    35                           41.7
    30                           34.2
    25                           27.7
    20                           22.0
    15                           17.5
    10                           13.4
      5                            10.0

Regards,
Don

FGT. . . . . . . . . . P H O T O - - G A L L E R Y


Fig 1 HOW GEM foil works


Fig 2 Filed lines through GEM foil


Fig 3 triple GEM HV


Fig 4 FOM for AL vs. lepton eta & PT, RHICBOS, GSRV-STD


Fig 5,Graphics courtesy of Tai Sakuma, MIT

 


Fig 6,Graphics courtesy of Jim Kelsey, MIT

more plots like this is here PPT , PDF presented at BNL, May 16, 2008.


 Fig 7. Assembled setup for mechanical and electrical test for Quadrant STAR/FQT/FEE

 


See other (large) photos below

 

 


 Fig 8. Y2008, full STAR


 Fig 9. UPGR16, full STAR


 Fig 10. UPGR16,inner trackers , side view


 Fig 10. UPGR16,inner trackers , side view


 Fig 11. Full size GEM foil , December 2008

 Fig 12. APV bonding, Januar 2009

Fig 13a-d. Photos of the APV-on-a-cable test setup for FGT (full size in attachments at the bottom), May 2009.

FGT. . . . . . . . . . S O F T W A R E

Current Software task list. Manpower and results

 docs.google.com/spreadsheet/ccc

 

 

 

 

Database Access

How to access database:

  • Instantiate StFgtDbMaker ->  StFgtDbMaker *myStFgtDbMaker=new StFgtDbMaker();
  • Then get tables ->  StFgtDb * fgtTables = myStFgtDbMaker->getDbTables();
  • Now you can go get whatever geometry stuff you might need from StFgtDb.  For example:
    • fgtTables->getPhysicalCoordinateFromGeoId(geoId, &disc, &quad, &layer, &ordinate, &lower, &upper);
    • fgtTables->getGeoIdfromElecCoord(rdo, arm, apv, ch);

Electronic ID Formula:

    if ( apv > 11 ) apv = apv - 2;

    ElectId = channel + 128 * ( apv + 20 * (arm + 6 * ( rdo - 1) ) );

 

General Database Info (from Dmitry)

1. For real .daq files processing, timestamp is taken from event - it cannot be set by user. For example, if event timestamp is XYZ, then db maker will get db entries with time validity spanning from [XYZ - some_time_1] to [XYZ + some_time_2] where some_time1 is the beginTime of the db entry received, and some_time_2 is the beginTime of the next db entry with beginTime > XYZ.

2. DBV option (in chain) only freezes validity range, which means "do not consider calibrations uploaded later than DBVXXYYZZ". This allows to reproduce any past conditions. So, if you set DBV to today's date, you will get latest calibration dataset. If you set it to some past date (e.g. 2010-01-01) then you will get only those datasets which were uploaded before 2010-01-01. So, tables are read using both beginTime and entryTime..

FGT Pedestal Maker, Reader, and Plotter

See Renee's instructions how to create and upload pedestals/status attached
-----------------

I had hoped to write this tutoral once all code was in CVS and I had automated all of the loading and writing scripts. Unfortunately these conditions are only partially fullfilled at this time, so this procedure describes how to make pedestal and status files needed to load to the database:

  • mkdir FgtPed
  • cd FgtPed
  • stardev
  • cvs co StRoot/StFgtPool/StFgtRawDaqReader
  • cvs co StRoot/StFgtPool/StFgtCosmicTestStandGeom
  • cvs co StRoot/StFgtPool/StFgtPedMaker
  • cvs co StRoot/StFgtPool/StFgtStatusMaker
  • cvs co StRoot/StFgtPool/StFgtQaMakers
  • cons
  • cvs co StRoot/StFgtPool/StFgtQaMakers/macro/makeFgtPedAndStat.C

You will need to open makeFgtPedAndStat.C and set the database time manually (next step is to automate this).  This timestamp is used to get the correct mapping:
  • dbMkr->SetDateTime(20121108,000000);
You also need to set the file and output file name fields at the top, but this is easily done dynamically if you wish.  Next simply run the macro :  root4star -b -q makeFgtPedAndStat.C.  Eight files will be part of the output:
  • Filename.FGT-ped-DB.dat
  • Filename.FGT-ped-stat-info.txt
  • Filename.FGT-ped-stat.pdf
  • Filename.FGT-ped-stat.ps
  • Filename.FGT-ped-stat.root
  • Filename.FGT-ped-stat.txt
  • Filename.FGT-stat-DB.dat
  • fgtMapDump.csv
The .dat files need to be loaded to the database using the macros
  • cvs co StRoot/StFgtUtil/database/macros/write_fgt_pedestal.C
  • cvs co StRoot/StFgtUtil/database/macros/write_fgt_status.C
  • cvs co StRoot/StFgtUtil/database/macros/fgtPedestal.h
  • cvs co StRoot/StFgtUtil/database/macros/fgtStatus.h
Now you need to open each of these macros and set the database time and file input correctly before running via the standard root4star -b -q write_fgt_pedestal.C.



Software for computing (making), reading (from file or DB) and plotting pedistals has been written.  The DB functionality is not fully implemented as of Jan 10, 2012.

 


Files

The current code for reading and writing pedistals is contained in the following files

$CVSROOT/offline/StFgtDevel/StRoot/StFgtPedMaker/StFgtPedMaker.h
$CVSROOT/offline/StFgtDevel/StRoot/StFgtPedMaker/StFgtPedMaker.cxx
$CVSROOT/offline/StFgtDevel/StRoot/StFgtPedMaker/StFgtPedReader.h
$CVSROOT/offline/StFgtDevel/StRoot/StFgtPedMaker/StFgtPedReader.cxx

An example of using the pedistal maker is in the file

$CVSROOT/offline/StFgtDevel/StRoot/StFgtPedMaker/macro/makeCosmicPeds.C

An example of using the pedistal reader is in the file

$CVSROOT/offline/StFgtDevel/StRoot/StFgtPool/StFgtPedPlotter/macro/plotPedsFromFile.C

An auxillary class to make a nice plot of pedistals is found in the files

$CVSROOT/offline/StFgtDevel/StRoot/StFgtPool/StFgtPedPlotter/StFgtPedPlotter.h
$CVSROOT/offline/StFgtDevel/StRoot/StFgtPool/StFgtPedPlotter/StFgtPedPlotter.cxx

After the software review, it is expected to move these files to StRoot instead of offline/StFgtDevel/StRoot


StFgtPedMaker

The StFgtPedMaker is designed to use the FGT online containers in StEvent.  The pedistals are the mean ADC value over all events processed by the chain, while the "RMS" is actually the standard deviation.  Running sums are computed in the StFgtPedMaker::Make function, and the final values are computed in ::Finish member function.  The values can then be written to a file, which contains four columns: (1) geoId of the strip (2) timebin (3) pedistal, i.e. mean ADC (4) RMS, i.e. st. dev.

The pedistal maker has the following user functions to modify the options:

   void setToSaveToFile( const Char_t* filename );
   void setToSaveToDb( Bool_t doIt = 1 );
   void setTimeBinMask( Short_t mask = 0xFF );

To save to file, one uses the "setToSaveToFile" function and passes the filename to which the information should be saved.  The "setToSaveToDb" function is not yet implemented.  It was decided not to allow this functionality in this class, but rather have a decidated macro to upload a text file generated by this class into the DB.  The time bin mask is set via the "setTimeBinMask" function.  All time bins which are flagged "false" in the mask will be ignored.  Note: time bin 0x01 is the 0th time bin, 0x10 is the 4th time bin, etc. 

The status of the strips (e.g. dead, broken, and/or hot strips) is not considered in making the pedistals.  All pedistals are computed for the time bins specified in the time bin mask.  As status of the strips is given by the StFgtStatusMaker/Reader, it is expected that the code querying the StFgtPedReader for a pedistal will also query the StFgtStatusReader for a status of the strip, and then choose to act accordingly.  In this manner, the status does not have to be computed before computing the pedistals, but instead should be computed before using the pedistal information.


StFgtPedReader

It was anticipated that all calls for pedistals, in all software, would use the StFgtPedReader.  The StFgtPedReader initially either loads the pedistals from file, or from the database, and holds them in an associative array, allowing both sparse data and for fast look ups.  In future versions, one could change the implimentation to a static array, if one desired faster processing but a larger memory imprint.  The code has the following accessor function, to read the time bine for a given geoId and time bin:

   // accessor: input is geoId and timebin, output is ped and
   // st. dev. (err).  Returns error if pedistal not found for given geoId and timebin
   Int_t getPed( Int_t geoId, Int_t timebin, Float_t& ped, Float_t& err ) const;

One can also set a time bin mask via

   void setTimeBinMask( Short_t mask = 0xFF );

Time bins with bits set to false will be ignored.  The fewer time bins loaded, the faster the initial load and the faster the look up time for each individual geoId afterwards.

The DB interface still needs to be programmed as of Jan 10, 2012.


StFgtPedPlotter

This produces a nice plot of the pedistals for a given quadrant (10 APVs).  The procedure is straight forward. See the macro and the code for an example of how this is done.  Note: the ped. plotter gives an example of how to use the ped. reader.


Comments

Usually 2,000 are used to compute pedistals.  The amount of time taken by the StFgtPedReader/Maker is significantly less than the amount of time used by the RawMaker to create the FGT containers in the StEvent and read the DAQ file from disk, and therefore can be considered negligible for the present.

An example pedistal file is attached.  This file is from the cosmic test stand, when quadrants 008, 018, 007 were on the top, middle, and bottom possition, respectively.  Plots of typical pedistal RMS can be found on page 1 of the QA plots produced during the cosmic test stand.  The base directory is http://www.star.bnl.gov/protected/spin/sgliske/fgtCosmicQA/, from which you can then select a quadrant, and then select a .pdf file.  The files are named via the quandrant and the time the data was taken.

FGT Simulation

Random notes from email exchanges:

 

A bfc that produces muDsts from simulation files looks like this
root4star -b bfc.C'(10,"MakeEvent,ITTF,NoSsdIt,NoSvtIt,Idst,VFPPVnoCTB,logger,-EventQA,-dstout,tags,Tree,EvOut,analysis,dEdxY2,IdTruth,useInTracker,-hitfilt,tpcDB,TpcHitMover,TpxClu,McAna,fzin,y2012,tpcrs,geant,geantout,beamLine,eemcDb,McEvOut,bigbig,emcY2,EEfs,bbcSim,ctf,-CMuDST,sdt20120501.060500","pp200_QCDprodMBc.fzd")' -q > & Log1

There is  an fzd file in avossen/tmp/4jason/

 

The code is available at
StRoot/StFgtSimulator/
and should also be available as

The bfc to run it is in StRoot/StFgtSimulator/macros/bfc.C
You can run it from the StFgtDevel dir with the following
command line:

%root4star -b
StRoot/StFgtSimulator/macros/bfc.C'(10,"MakeEvent,ITTF,NoSsdIt,NoSvtIt,Idst,VFPPVnoCTB,\
  logger,-EventQA,-dstout,tags,Tree,EvOut,analysis,dEdxY2,\
  IdTruth,useInTracker,-hitfilt,tpcDB,TpcHitMover,TpxClu,\
  McAna,fzin,y2012,tpcrs,geant,geantout,beamLine,eemcDb,\
  McEvOut,bigbig,emcY2,EEfs,bbcSim,ctf,-CMuDST","pp200_QCDprodMBc.fzd")'

 

 

Legend for Status in DB

Strip Status

Status bits are failure states, i.e. status of 0 is good, anything else is bad. Strip status bits are defined as

  • bit 1: pedestal out of range (current range is 100-1200 ADC)
  • bit 2: RMS out of range (current range is 10-80 ADC)
  • bit 3: Fraction of integral near pedestal value (i.e +/- 1 RMS of the pedestal) out of range (current range is 0.6 to 0.95)
  • bit 4: not used
  • bit 5: APV chip bad (threshold is currently 64 dead strips)
  • bit 6: strip not connected

Note, for bit 5, all strips are set to have this bit fail if more than the threshold number of strips on this APV failed the tests corresponding to bits 1-3.

Offline Software

Getting started with plots for the FGT

(some old documentation on how to read MuDSTs: drupal.star.bnl.gov/STAR/blog/avossen/2012/apr/26/how-read-mudsts)
Prepare your libraries
If you're brand new or starting fresh directory for FGT, you'll need to check out some files... This is a list of all the offline FGT software you're likely to need for whatever it is you're working on...
> mkdir mydir
> cd mydir
> cvs co StRoot/RTS
> cvs co StRoot/St_base
> cvs co StRoot/StEvent
> cvs co StRoot/StFgtA2CMaker
> cvs co StRoot/StFgtClusterMaker
> cvs co StRoot/StFgtDbMaker
> cvs co StRoot/StFgtPool
> cvs co StRoot/StFgtRawMaker
> cvs co offline/StFgtDevel/StRoot/StMuDSTMaker

> ln -s offline/StFgtDevel/StRoot/StFgtMuDSTMaker/ StRoot/StFgtMuDSTMaker

The last step is necessary since StFgtMuDSTMaker is not yet in devel.
Make sure you are in the proper STAR version (you want "development") and compile...
> starver dev
> cons

Pick your data
After your libraries installed correctly, pick a daq file for your FGT studies... (If you're using MuDST files this will be different..)
> ls /star/data03/daq/2012/xxx/13xxxyyy
where 13xxxyyy is the run number you want. (If the run number you want isn't there, restore the daq files yourself or ask somebody to do it.)
Before running over data, make sure to run klog to ensure you get a token to communicate with the database..
> klog

>For MuDSTFiles the corresponding #define directive in StFgtPool/StFgtClusterTools/StFgtGeneralBase.h has to be set.

Run over the data
To fill all the plots you want, you'll need to run this command (when sitting in mydir)...
> cd mydir
> root4star -b -q StRoot/StFgtPool/StFgtClusterTools/macros/agvEffs.C'("/star/data03/daq/2012/131/13173068p_rf/st_physics_13173068_raw_202001.root",10,10000,2)' > & output.txt
The above command will attempt to run over 10,000 events from the example daq file, using disc 2 as the disc that is removed for efficiency calculations. Piping the output to file is necessary in order to cut down on running time. On average, 10,000 events takes ~45 minutes as long as you use an output file.

Look at the plots
The agvEffs.C macro will output some .root files...
-clusterEff.root
-clusterPics.root contains visual "pictures" of the first 1000 clusters found in the daq file.
-pulses.root counts pulses in the electronics etc
-signalShapes.root contains a whole heck of a lot of plots... To see exactly all that is put into signalShapes.root, take a look at StFgtClusterTools/StFgtGenAVEMaker.cxx
There are some friendly macros to help you pull out the plots you want in an organized way. Run these guys to output a whole ton of .png files. A few examples are...
> root4star -b -q StRoot/StFgtPool/StFgtClusterTools/macros/saveSignalChar.C'("signalShapes.root")' //this will output histograms per quadrant
> root4star -b -q StRoot/StFgtPool/StFgtClusterTools/macros/saveSignalCharAPV.C'("signalShapes.root")' //this will output histograms per APV
> root4star -b -q StRoot/StFgtPool/StFgtClusterTools/macros/saveClusterSizes.C'("signalShapes.root")' //this will output cluster size histograms per quadrant
For now it's been most convenient to just dump the .png files into your protected directory but hopefully something a little more elegant is on its way very soon...

Streamlining the process
Right now we have a shell script that pulls daq files name from a list and then runs over them one after the other, dumping the output .root files into a directory. Look around for things like "runChain.sh" and "l13173068.list" if you want to have a go at that.
> ./runChain.sh > & output.txt
Coming soon: pre-written xml job for STAR scheduler.

Available data sets
Most recent runs are located in http://www.star.bnl.gov/protected/spin/ezarndt/fgt/
Coming soon: plots better organized into a scroll-friendly format.

Online Software

The online software uses the 'JPlot' framework:

 

> cvs co OnlTools/Jevp

> cvs co OnlTools/PDFUtil

> cvs co StRoot/RTS

> cvs co StRoot/StDaqLib

>cvs co StRoot/StEvent

The framework currently only compiles correctly with the 'pro' library version:

> starver pro

> cons

 

To run do:

> OnlTools/Jevp/launch fgtBuilder -file filename -pdf outputfilename.pdf

Jevp instructions can be found in

OnlTools/Jevp/readme.txt

The fgt specific code is in OnlTools/Jevp/StJevpBuilders/fgtBuilder.{h,cxx}

 

 

 

 

 

 

Test Stand

FGTEventDisplay Overview and Instructions

At the moment FGTEventDisplay incorporates much of the code that we've been using to generate plots, and allows the viewing of individual events. It's certainly not perfect (and it will likely be replaced at some point in the near future), but since it contains this functionality, I thought I might give a brief overview of what it can currently do and how to use it.

Here's what it can do:

* Calculate and display pedestals

Currently, pedestals are calculated from the first 1000 events in a file. These pedestals are only calculated the first time a daq file is viewed using the FGTEventDisplay, when the APV range is changed, and when you force the pedestals to be recalculated. Otherwise, it saves the pedestals to a file in the FGTEventDisplay directory.

When the pedestals are displayed, they are displayed as ADC response per channel. Three graphs are shown with error bars, at 1, 2 and 3 sigmas. Many of the algorithms in the code use the three sigma cutoff when accepting an ADC response for use.

Figure 1: Example pedestal plot

* Generate Radio Hits graphs

The code can generate and save radio hits plots, similar to those that I have been posting to track down the APV mapping problem. The graphs that are generated are just raw 2-D histograms that are then saved to root files. The processing done to improve the appearance of those graphs as well as applying the device boundaries are actually done by a utility macro included with FGTEventDisplay. This macro is called Display.C and is in the same directory as FGTEventDisplay.

Note that all 7 time bins are accumulated by this code separately, and all 7 time bins are saved as separate histograms to the root file.

There are two types of radio hits graphs that are generated. The first plots only the maximum hits. The algorithm finds the maximum value for each event that is above the pedestal 3*sigma and then fills that location in the histogram/radio plot. The second algorithm finds all values that exceed 3*sigma above pedestal and then fills those locations in the histogram/radio plot. These two types of graphs are saved in separate root files.

Figure 2: Example max hits plot

Figure 3: Example all r/phi matches plot

* Generate ADC Response graphs

This code generates and saves per-phi, per-r, and per-channel ADC response plots. Once again, these are just 2-D histograms that are then saved to a root file, and processing to improve the appearance of these plots was done in Display.C. The algorithm selects all ADC responses greater than 3-sigma over pedestal for each event. The channel number in this case is the APV number (offset so that all APV ranges start at 0) times 128 plus the actual channel number. Phi and R values are determined based on the mapping that is included with the FGTEventDisplay (this is located in fgt_mapping.txt). Once again, note that all 7 time bins are accumulated by this code separately, and all 7 time bins are saved as separate histograms to the root file.

Figure 4: Example ADC response vs channel plot

Figure 5: Example ADC response vs phi plot

Figure 6: Example ADC response vs r plot

* Generate Raw ADC Response graphs

This code generates and saves per-phi, per-r, and per-channel ADC response plots, very similar to the above, but it does not apply pedestal subtraction or thresholds. The channel number is still the APV number (offset so that all APV ranges start at 0) times 128 plus the actual channel number. Phi and R values are determined based on the mapping that is included with the FGTEventDisplay (this is located in fgt_mapping.txt). Once again, note that all 7 time bins are accumulated by this code separately, and all 7 time bins are saved as separate histograms to the root file.

Figure 7: Example raw ADC response vs channel plot

Figure 8: Example raw ADC response vs phi plot

Figure 9: Example raw ADC response vs r plot

* Display individual events

FGTEventDisplay allows you to iterate both forward and (slowly) backwards through individual events in a daq file, as well as jump (slowly) to individual events. For each event, at least three graphs are shown, possibly four. The three that are always shown are ADC response versus R, ADC response versus Phi, and ADC response versus channel (using the same channel calculation method and mapping as described earlier).

The fourth graph will only display if the values for the current event are found that exceed 3*sigma over pedestal. It shows all possible hit locations in R and Phi for these values. Currently this is not a radio plot, but this may change in the future for clarity.

The time bin selected for display here is always the fourth time bin.

Figure 10: Example default event display plot



Anselm's clustering code is currently in a developmental version of FGTEventDisplay. We are working on incorporating a correction for common mode noise, relative R/Phi gains, and gain matching into this clustering code.


Here are instructions for downloading, compiling, and using FGTEventDisplay:

To download:

FGTEventDisplay is currently stored in a googlecode SVN repository. In order to use this repository, you have to set up your svn proxy properly so that you can contact the googlecode.com (this has already been done on fgt-ops). Probably the easiest way to do this is to attempt to download the code first by issuing the command:

svn co https://fgt-daq-reader.googlecode.com/svn/trunk/FGTEventDisplay FGTEventDisplay

This will almost certainly fail, but it should create the file ~/.subversion/servers. You will need to edit that file and by adding the following two lines to the end of the file:

http-proxy-host=proxy.sec.bnl.local
http-proxy-port=3128


Once that is done, try issuing the command again. This time it should work (let me know if it doesn't), and it should create a directory FGTEventDisplay containing all the program files. From then on you can just update that working copy to get updates by issuing the command

svn update

in the FGTEventDisplay directory. This should automatically merge changes into your files, without clobbering your own changes, although if there are conflicts you may have trouble.

If you want or need access to this repository, please send e-mail to Dr. Fatemi and let her know. At that point she'll probably ask me to add you, and I'll try and remember how to do that.

To compile:

Go into your FGTEventDisplay directory and issue the command:

make

Compilation stuff should happen, and you should be left with an FGTEventDisplay executable.

Please note that you should NOT use Rts_Example.sh to compile. I can't guarantee that it will work, and it is included in the repository only for historical reasons (because, historically, we've been too lazy to remove it).

To run:

Go into your FGTEventDisplay directory (this is IMPORTANT. . . the code will not run from another directory) and issue the command:

./FGTEventDisplay <location of DAQ file>

Replacing <location of DAQ file> with the actual path to a DAQ file.

This will start the program. The code will either automatically generate or load pedestals, depending on whether or not they have already been calculated by some previous run.

Then the program will show the main text menu. The menu lists most of your options, and most of them should be pretty straight forward.

However, there are a few things that should be mentioned. First, by default, the code will assume that you are using the APV range 17 through 21. If you are using a different range, you need to set that difference in the program options, and currently the software only supports ranges 17 through 21 and 12 through 16. To get to options, just type "o" at the main menu. Once there, type "a" to change the APV range. then press "q" to return to the main menu. Doing this will now AUTOMATICALLY force pedestal recalculation, so at this point you should be able to use the code normally.

Also, in options you can tell the program to display bar graphs when displaying events (instead of scatter plots), and change the marker style in the scatter plots. These ONLY effect the event display.

Figure 11: Example default event display with bars


The event display plots do not currently allow any user interaction. This is unfortunate, and I'm planning on fixing it in the future, but right now nearly all x-windows events are ignored by that window, so resizing and clicking and even moving it off screen (for some window managers) will not work as expected.

The daq reader does not have a mechanism for iterating backwards, or a mechanism for jumping to an arbitrary event. As such, iterating backwards (using "h" or "k") may be very, very slow, as the program has to iterate forwards from the beginning of the daq file to the previous event. Similarly, though I have tried to make it as efficient as possible, jumping to an event may be very slow (although, jumping to an event *forward* of your current position in the file will start from your current position, so it should be more efficient).

When jumping to an event directly, you should use the event number that is displayed by the program in the main menu as you are iterating through the daq file. That event number should appear right above the command prompt.

Finally, many of the plots above are colorful and contoured. These are not the raw images that the FGTEventDisplay will produce. With the exception of the individual event display and the pedestal display, FGTEventDisplay will produce root files containing histograms. Generating the plot for these histograms must be done separately. A macro, Display.C, is included with FGTEventDisplay that can be used to generate these nice, colorful plots, however it currently requires modification to function with every possible root file and contained histogram.

 

Organization

FGT. . . . . . . . . . V A R I A

  1. Frank's Web page at MIT
  2. Dave's Web page Argonne

  3. ccc

 

TPC resistor chain at phi=106 deg

 Here is what we know about TPC resistor chain in IFC positioned at 106 deg in phi.

  •  the foil covering resistors  is made of the Al plus Kapton is 0.09 percent of a radiation length thick for a straight through track.
  • material is used for to round cylinders  supporting that foil is made of 1" pipe made from G10, wall thickness ~ 1mm
  • Foils structure is described on TPC page we are using one capton foil with Al stripes
    http://www.star.bnl.gov/public/tpc/tpc.html
  • resistors: between stripes we put 2MoM resistor, consisting of 2  with 1 MoM nominal- see picture in attachment.
    i don't know a power, but it is 4 mm diameter and 13 mm  ceramic body.
    there are 360 ONE MoM resistors on each side of TPC We have 182 stripes to define uniform field and between each pair of stripes we put 2 MoM

 


As seen from the East toward West:

BAD drawing:

Good drawing:

 

 


As seen from the West toward East:

 

FGT. . . . . . . . . . x -T R A S H (node for recycling)

Any child pages belonging here is a trash.
Note only the owner can recycle them by attaching to a new mother-page and changing the title,URL, and content.

Jan

fgt-subpage-test-Renee

this is my link to my previous blog

my trash1- jan

 this age can be used for some testes

trash1

 Bhla Bhla

 

Deleted Documents

Deleted documents.