Photon hadron correlations task list

• pp run periods selection
  • QA calorimeter : Dana (taks 1), Xiangrong
  • Run selection with PHOS triggered : Renzhuo (task 1)
  • QA TPC : What is the TPC performance? Check RTC / run
• pp (PbPb) charged track selection, ESD-AOD : Dana (task 2)
  • fake tracks at high pt
  • find best selection criteria ( hybrid tracks as jet and correlation groups ?)
  • define track momentum ranges and acceptance
    • We should define the region in eta where we want to correlate with tracks
    • Is a maximum pT cut needed to avoid fakes ?
• pp trigger particle selection
  • study the selection (pt, eta ranges) of the trigger particle
  • trigger region and associated pt bins: Nicolas (task2)
    • Correlation ranges in xE and zT
    • pT reach, fake tracks at high pT
• MC productions
  • Selection of available MC runs suitable for correlation studies
• EMCal clusterization (for PbPb, more studies to be done)
  • Pi0 analysis : V1+unfolding needs a final check Gustavo (next week)
  • Pi0/Eta event by event via cluster splitting with V1 : check (?)
  • EMCal charged clusters vetoing
    • pp : Gustavo (done),
    • PbPb : further checks with data driven cluster selection in PbPb are needed
  • Neutral meson identification event by event via pair cuts : Tuning needed
    • check purity of mass cut range, variation with energy might be needed
    • the aperture angle need more checks
  • Neutral meson identification via cluster splitting in EMCAL
    • Need realistic MC for final assesment
    • for E< 20 GeV: Gustavo (done)
    • Splitting at high energy (E>20 GeV) of clusters might introduce too much contamination from wrong splits. It needs a careful look
• Photon selection / shower shape
  • MC tuning for photon pid: Nicolas (task 1), Mauro (task 1)
    • Cut on pt of particles in cone
    • a la Mauro : sum of the energy in trigger cone and background region, subtract and apply a cut on the remaining energy
    • What MC can be used for PID studies or correlation studies ?
    • Need to revise, adapt to the new mixing frame, or to use a "hand made mixing" like for pi0 analysis. If needed...
  • isolation
    • Isolation with track, clusters or tracks+clusters or just cells : Nicolas (task 3)
    • quantify impact of the acceptance (density method) : Nicolas
    • what is the effect on the efficiency
    • Effect of fiducial cuts on isolation decay/pi0
    • how to estimate systematic errors
    • impact of QA on isolation Alexis
    • isolation with method 2 : Mauro (task 2)
    • Systematic studies to be (re)done in pp (and PbPb separatedly) using data driven methods (decay photon, or pi0 cluster identification) or MC (embedded).
    • Do we need to apply flow corrections? If we concentrate in high pT maybe not.
  • Converted photon id (needed ?)
  • track matching : Gustavo
    • what particles are in the cone ? good clusters all have a track matched ?
• Efficiency
  • Pi0, eta and decay photon tagging
    • check systematics and efficiency of EMCal cuts
    • efficiency, purity and background estimation : Xiangrong (task 1)
  • (need to check in PbPb)
  • Azimuthal eff correction : Dana (task 3)
• Embedding :This might need of a common production and discussion with other groups (PWGJE, PWGCF)
• Background and systematic uncertainties
  • trigger : decay and hadron contamination
    • need simulations with realistic pi0 spectrum
    • how to propagate the estimated background
  • xt, zt; how to estimate syst uncertainties due to background and underlying event subtraction : Nicolas (task 4 : xE, zT systematic errors, contamination estimation)
  • delta phi
    • pedestal subtraction : di hadron paper uses 3 different approaches. Avoid mixed events unless non uniform phi of tracks
    • cluster-track correlation eff estimation
      • how ?
      • how to propagate to Iaa ?
      • Contribution to flow ?
      • track eff : check eta-phi eff for diff pt and not integrated
      • how to estimate syst uncertainty due to background ?
  • non-Pi0 band correlations vs pi0 band : Hongsheng (task 1) and Xiangrong (task 2)
• Comparison to simulation, to 2.76 pp data ?

photon spectra

• Triggered spectra normalization : Alexis (task 2)
• Direct photon predictions : Alexis (task 2)
• Direct photon INCNLO predictions : Hugues (task 1)
• QA : Marie (task 1)
• time cuts : Marie (task 2)

-- CatherineSilvestre - 06-Mar-2012