2009.11.17 BEMC sampling fraction: energy dependence

Monte-Carlo setup:

  • Throwing one photon per event
  • Full y2009 STAR geometry configurations with LOW_EM option
  • Throw particles flat in eta (-1,1), phi (0, 2pi),
    with energy steps: 10, 20, 30, 40, and 50 GeV with flat (+/-0.5 GeV) spread
  • bfc.C options:
  • Use fixed (7%) sampling fraction in StEmcSimpleSimulator.cxx
    mSF[0] = 1/0.07;
    mSF[1] = 0.;
    mSF[2] = 0.;
  • Vertex z=0
  • 50K/per particle type

data base settings (same settings in bfc.C (Jan's trick) and in my MuDst reader):

Note: for BEMC ideal pedSigma set to 0, so effectively
there is no effect when I apply 3-sigma threshold above pedestal.

Figure 1: Rapidity cuts study (no eta cuts, no cuts on otliers in this figure)

Figure 2: Sampling fraction (0.07*E_reco/E_thrown) distribution
E_reco is the total energy in the BEMC towers from mMuDstMaker->muDst()->muEmcCollection()
E_thrown energy of the thrown photon from tne Geant record
Cuts: |eta| < 0.97 && |eta|>0.01 && s.f. > 0.055
s.f. distribution on the log scale