2010.07.16 Pythia/BFC gamma-filter bias tests with realistic gain variation

Related inks:

• Previous study with ideal gains and gain shift only of +10%
• Tests of L2e-gamma trigger emulation with full Pythia+Geant Monte-Carlo
• Previous study before filter emulator fixes
• QCD and gamma-jet data samples are described here
  (filter parameters are listed below)

Number of generated events per partnic pt bin (pt binsa are: 2-3, 3-4, 4-6, 6-9, 9-15, 15-35):
gamma-jets (2-4): 25K/bin
gamma-jets (4-35): 12.5K/bin
QCD(2-4): 50K/bin
QCD(4-35): 25K/bin

Pythia filter configuration

StEemcGammaFilter:: running the TEST mode (accepting all events). Set mFilterMode=1 to actually reject events
StEemcGammaFilter:: mConeRadius 0.22 mSeedThreshold 3.8 mClusterThreshold 5 mEtaLow 0.95 mEtaHigh 2.1 mMaxVertex 120
StEemcGammaFilter:: mCalDepth 279.5 mMinPartEnergy 1e-05 mHadronScale 1 mFilterMode 0 mPrintLevel 1

BFC filter configuration

StChain:INFO - Init() : Using gamma filter on the EEMC
StChain:INFO - Init() : EEMC Sampling Fraction = 0.05
StChain:INFO - Init() : Seed energy threshold = 3.8 GeV
StChain:INFO - Init() : Cluster eT threshold = 5 GeV
StChain:INFO - Init() : Maximum vertex = +/- 120 cm
StChain:INFO - Init() : Running the TEST mode (accepting all events). Set mFilterMode=1 to actually reject events in BFC

StEEmcSlowMaker configuration with realistic gain shift/smearing

Figure 1: Error for gains from MIP study minus ideal
Data digitized from Scott's presentation at 2008 Calibartion workshop

BFC:INFO - setTowerGainSpread(): gain spread: 0.1; gain mean value: 1.05 (Fig. 1,3 only)
BFC:INFO - setTowerGainSpread(): gain spread: 0.1; gain mean value: 0.95 (Fig. 2,4 and below)

GammaMaker configuration

runSimuGammaTreeMaker():: GammaMaker config: ConeRadius 0.7 ClusterEtThreshold 5.5 SeedEnergyThreshold 4.2 ClusterEnergyThreshold 5.5 BsmdRange 0.05237 EsmdR ange 20

A2Emaker configuration

StEEmcA2EMaker *EEanalysis = new StEEmcA2EMaker("mEEanalysis");
EEanalysis->threshold(3.0, 0); // tower threshold (ped+N sigma)
EEanalysis->threshold(3.0, 1); // pre1 threshold
EEanalysis->threshold(3.0, 2); // pre2 threshold
EEanalysis->threshold(3.0, 3); // post threshold
EEanalysis->threshold(3.0, 4); // smdu threshold
EEanalysis->threshold(3.0, 5); // smdv threshold

Trigger configuration

(Includes all recent fixes to trigger emulator configuration/software)
emulated L2E-gamma trigger for Run 2006 [eemc-http-mb-l2gamma:: id 137641]
Trigger conditions:
cluster Et (3x3) = 5.2GeV
seed Et = 3.7GeV

Accept/Reject relative to the total number of offline selected events

Definition: offline selected events are events which satisfy to the following conditions:

• Online condition (L2E-gamma trigger fired)
• Reconstructed vetrex (|v_z|<120cm)
• Offline condition (at least one gammaMaker candidate found)

Figure 2:
(upper plots) Gamma candidate yields vs. candidate pt (all partonic pt bins, no pt weights)
(lower plots) False rejection [histograms in the upper panel scaled by L2E-gamma-trigger yield (shown in blue)]
StEEmcSlowMaker configured with +5% (scale factor=1.05) gain shifts and 0.1 sigma
Previous plots: 125K events per pt-bin, 250K/pt-bin
(figure below combines previous statisitcs + 18K for partonic pt=6-9 and pt=9-15 GeV bins)

Figure 2b: Filter bias per partonic pt bin (QCD simulations only)

Figure 3: Same as Fig. 1 with gain shift=0.95 and sigma=0.1

Figure 4: Same as Fig. 1 vs. candidate eta with gain shift=1.05 and sigma=0.1

Figure 5: Same as Fig. 1 vs. candidate eta with gain shift=0.95, sigma=0.1