Extracting gammajet cross section at forward rapidity from pp@200GeV collisions
Analysis overview
 Data samples, event selection, luminosity determination
 Isolating photonjet events
 Transverse shower shape analysis
 Isolation cuts
 Cut optimization
 Trigger effects study
 Data to MonteCarlo comparison/normalization and raw yields
 Acceptance/efficiency corrections
 Corrected yields
 Background subtraction
 Systematic uncertainties
 Comparison with theory
Data samples, event selection, luminosity determination
Real data, and signal/background MonteCarlo samples:

pp@200GeV collisions, STAR produnctionLong.
Trigger: eemchttpmbL2gamma [id:137641] (L ~ 3.164 pb^1) 
Pythia prompt photon (signal) MonteCarlo sample.
Filtered Prompt Photon p6410EemcGammaFilter.
Partonic pt range 225 GeV. 
Pythia 2>2 hard QCD processes (background) MonteCarlo sample.
Filtered QCD p6410EemcGammaFilter.
Partonic pt range 225 GeV.
Isolating photonjet events
 Shower shape analysis
 Isolation cuts
 Energy clustering (2x1 vs. 2x2 vs. 3x3, cluster energy vs. rapidity)
 Charge particle veto
 photon and jet pt balance
 Tower multiplicity
 Cut optimization with LDA.
Input variables (list can be expanded): Energy fraction in 3x3 cluster within a r=0.7 radius, E_3x3/E_0.7
 Photonjet pt balance, [pt_gammapt_jet]/pt_gamma
 Number of charge tracks within r=0.7 around gamma candidate
 Number of Endcap towers fired within r=0.7 around gamma candidate
 Number of Barrel towers fired within r=0.7 around gamma candidate
 Shower shape analysis: distance to 80% cut line
 Energy fraction in E_2x1 and E_2x2 witin E_3x3
 Energy in postshower layer under 3x3 tower patch
 Tower energy in 3x3 patch
 SMDu/v energy in 25 central strips
 SMDu/v peak energy (in 5 central strips)
Trigger effects study
No studies yet
 Trigger effects vs pt
 Trigger effects vs eta
 What else?
Data to MonteCarlo comparison/normalization and raw yields
 Overall data to MC normalization based on vertex z distribution
 Data to MC comparison of raw yield in various detector subsystems
 Uncorrected yields optimized with different efficiency/purity
Acceptance/efficiency corrections
No studies yet
 What needs to be studied for acceptance/efficiency effects?
 Converting reconstructed photon (jet) energy/momentum to the true one
 Reconstruction efficiency vs. rapidity, pt, etc
Corrected yields
No studies yet
 Produce acceptance/efficiency corrected yields
Background subtraction
No studies yet
 Statistical background subtraction based on Pythia+GEANT MonteCarlo
 Estimate systematic uncertainties due to background subtraction
Systematic uncertainties
No studies yet
 Calorimeter energy resolution
 Trigger bias
 Other effects
Comparison with theory
No comparison yet
 Request for pQCD calculations at forward rapidity
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