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Existing Framework For FGT Simulations

Updated on Mon, 2008-01-28 21:16. Originally created by betan on 2008-01-09 23:12. Under:

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.

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