Photon-jets

Ilya Selyuzhenkov for the STAR Collaboration

Photon-jet reconstruction software documentation

Analysis links

Year 2010

• September 2010
  1. 2010/09/23: Neutral energy jet shape comparison for various tunes
  2. 2010/09/15: Data vs. official filtered MC: energy deposition in various EEMC layers
  3. 2010/09/13: Data vs. official gamma filtered Monte-Carlo: cluster energy ratios
  4. 2010/09/10: Data to MC comparison with official EEMC gamma filtered production
  5. 2010/09/08: First look at the official EEMC gamma filtered production
• August 2010
  1. 2010/08/10: Timestamps study for the EEMC gamma filtered simulation request
  2. 2010/08/09: PyTune comparison with gamma candidates from dijets: Perugia0 vs. Pro-PT0
• July 2010
  1. 2010/07/23: PyTune comparison with photon candidates: Perugia0 vs. Pro-PT0
  2. 2010/07/22: Run 6 EEMC gamma-filtered simulation request
  3. 2010/07/20: Updated EEMC simulation spreadsheet: prompt photons and QCD
  4. 2010/07/16: Pythia/BFC gamma-filter bias tests with realistic gain variation
  5. 2010/07/14: Pythia/BFC gamma-filter bias tests (vs. gamma pt, eta, energy, and phi)
  6. 2010/07/09: Table of L0-BBC, L0-EEMC, and L2Egamma triggers biases
  7. 2010/07/02: Tests of L2e-gamma trigger emulation with full Pythia+Geant Monte-Carlo
• June 2010
  1. 2010/06/30: Py-tunes (GEANT+L2e-gamma trigger) vs. Run 6 data
  2. 2010/06/28: Tests of L2e-gamma trigger emulation with single photon Monte-Carlo
  3. 2010/06/18: L2e-gamma trigger effect: Py-CDF-Tune-A, Py-Perugia0, and pp2006 data comparison
  4. 2010/06/17: Pythia TuneA/Perugia0 filtered MC vs. pp2006 data
  5. 2010/06/15: First look at data vs. TuneA/Perugia0 filtered MC

• May 2010
  1. 2010/05/28: Photon-jet candidates - Perugia vs. Tune A
  2. 2010/05/27: Run 6 and Run 9 jet Tree production: details specific to the photon-jet analysis
  3. 2010/05/13: Pythia filter QA after fixed "Eta -> -Eta" bug
  4. 2010/05/05: Starsim/bfc timing tests
  5. 2010/05/03: EEMC simulation spreadsheet: prompt photons and QCD
  6. 2010/05/03: Pythia/BFC filter biases vs. gamma candidate pt (with fixed gamma-maker)

• April 2010
  1. 2010/04/30: BFC and Pythia biases after gamma-maker 3x3 cluser fix has been updated
  2. 2010/04/17: Pythia/BFC gamma-filter accaptance vs. gamma candidate pt, energy, and eta
  3. 2010/04/17: BFC and Pythia QA: 10% gain shift: lowered thresholds
  4. 2010/04/09: BFC and Pythia Filter QA: +10% gain shift (after filter code peer review)

• March 2010
  1. 2010/03/02: Photon-jet simulation request (draft)

• February 2010
  1. 2010/02/16: Pythia and BFC filter QA vs. gamma candidate pt and eta
  2. 2010/02/12: Final Pythia and BFC EEMC-gamma-filter paramter settings
  3. 2010/02/11: BFC and Pythia Filter QA: +5% gain shift (no spread, mean=1.05)
  4. 2010/02/11: BFC and Pythia Filter QA: Gain study with "-5%" shift (mean=0.95, spread=0.05)
  5. 2010/02/09: BFC and Pythia gamma filters: accept/reject rates relative to triggered events
  6. 2010/02/08: Eemc-Gamma-Filter QA: QCD vs. gamma-jet ccept/reject rates

• January 2010
  1. 2010/01/18: EEMC response 2006 vs. 2009: typo in TPC volume size bug fix
  2. 2010/01/08: EEMC response 2006 vs. 2009: TPC sector cuts
  3. 2010/01/07: EEMC response to single photons with y2006h vs y2009a geometries
  4. 2010/01/04: y2006h vs y2009a EEMC pre-shower migration

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Year 2009

• December 2009
  1. 2009/12/20: Ecalgeo-v6.2: embedded LOW_EM cuts after TPC/EEMC overlap fix
  2. 2009/12/17: Ecalgeo-v6.2: embedded LOW_EM cuts in the calorimeter geometry
  3. 2009/12/08: Low EM timing study: 10KeV vs. 100KeV cut settings
  4. 2009/12/07: Low EM study: LOW_EM option, 100KeV cuts, and DCUTE=100KeV
  5. 2009/12/03: Photon-jet simulation request
• November 2009
  1. 2009/11/23: New EEMC geometry (CVS v6.1): y2006 vs. y2009 STAR configurations
  2. 2009/11/19: LOW_EM and EEMC time/event in starsim
  3. 2009/11/16: Tests of EEMC geometry, version 6.1: lead vs. mixture
  4. 2009/11/11: Tests of EEMC geometry, version 6.1
  5. 2009/11/06: new EEMC geometry: Pure lead and new SMD layers
  6. 2009/11/03: Jason EEMC geometry: Effect of ELED block change
  7. 2009/11/02: Jason EEMC geometry: results with and without LOW_EM options
• October 2009
  1. 2009/10/30: Jason EEMC geometry: Jason with ELED block from CVS file
  2. 2009/10/27: Jason EEMC geometry: comparison without LOW_EM option
  3. 2009/10/27: Jason EEMC geometry: effect of removing new SMD layers
  4. 2009/10/26: Jason vs. CVS EEMC: removed SMD layers
  5. 2009/10/20: Sampling fraction problem: full STAR vs. EEMC stand alone geometry
  6. 2009/10/16: Jason geometry file: Full STAR simulations (sampling fraction, shower shapes)
  7. 2009/10/13: Jason geometry tests: SMD energy, number of strip vs. thrown photon position
  8. 2009/10/12: Effect of added layers in Jason geometry file
  9. 2009/10/05: Volume id fix in Jason geometry file
  10. 2009/10/02: Jason vs. CVS EEMC geometry: sampling fraction and shower shapes
• September 2009
  1. 2009/09/11: Test of corrected EEMC geometry: LOW_EM cuts
  2. 2009/09/04: EEMC geometry tests: on-off SVT detector and EEMC slow-simulator
• August 2009
  1. 2009/08/27: Single particle MC with corrected geometry vs. eta-meson from data
  2. 2009/08/25: Corrected EEMC geometry: shower shapes
  3. 2009/08/24: Corrected EEMC geometry (bug 1618)
  4. 2009/08/17: Plan for extracting photon-jet cross section from pp@200GeV data
• July 2009
  1. 2009/07/20: EEMC tower response in Monte-Carlo (pt_reco vs. pt_true)
• June 2009
  1. 2009/06/22: CIPANP 2009 proceedings on "photon-jet coincidence measurements"
• May 2009
  1. 2009/05/31: CIPANP 2009 presentation on "photon-jet coincidence measurements"
  2. 2009/05/12: Various distributions after LDA cut at 70% efficiency (LDA Set1 vs. Set2 for various pre-shower bins)
  3. 2009/05/07: Photon-jets analysis with the Endcap Calorimeter (analysis status update for Spin PWG)
  4. 2009/05/06: Applying purity or efficiency driven cuts on LDA discriminant
  5. 2009/05/04: LDA: added more SMD info, 3x3 tower energy, correlation matrix
  6. 2009/05/03: Varying pt, eta cuts with LDA (LDA includes SMD, r2x1, r2x2, post-shower)
• April 2009
  1. 2009/04/28: LDA plus SMD analysis with pre-shower sorting
  2. 2009/04/22: Combining LDA with shower shape analysis
  3. 2009/04/17: The STAR spin program with long. polarized proton beams (seminar at Wayne State U.)
• March 2009
  1. 2009/03/26: Photon-jets with the STAR Endcap Calorimeter (STAR Collaboration Meeting at BNL)
  2. 2009/03/09: Application of the LDA and MLP classifiers for the cut optimization
  3. 2009/03/02: Neural network application for the cut optimization (zero try)
• February 2009
  1. 2009/02/19: Photon-jets from the Endcap Calorimeter (Analysis status update for Spin PWG)
  2. 2009/02/16: pp2006, pp2008, and mc2006: pt_jet>5GeV; pre-shower sorting
  3. 2009/02/12: CIPANP 2009 abstract
  4. 2009/02/09: pp2006, pp2008, and mc2006 comparison
  5. 2009/02/06: Pre-shower energy: Run6 vs. Run8 geometry
  6. 2009/02/03: Data to Monte-Carlo matching: pt_jet>7GeV vs. no pt_jet cut
  7. 2009/02/02: Data to Monte-Carlo matching: fudge factor 1.24 (no pt_jet cuts, no pre-shower cuts)
• January 2009
  1. 2009/01/27: Away side jet and partonic pt contributions (fiducial cuts: |eta_jet| < 0.7, pre1<10MeV)
  2. 2009/01/27: Away side jet and partonic pt contributions: pt_jet>7GeV (detector |eta_jet| < 0.8)
  3. 2009/01/20: Data to Monte-Carlo normalization (pt and vertex z distributions, no isolation cuts)
  4. 2009/01/08: Away side jet pt vs. photon pt (no isolation cuts)

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Year 2008

• December 2008
  1. 2008/12/19: Parton pt distribution: QCD vs. gamma-jet events (more QCD statistics from Michael)
  2. 2008/12/16: Effect of L2gamma trigger in simulations
  3. 2008/12/11: ppProduction2008 QA (presentation for Spin PWG)
  4. 2008/12/08: pp2008 data QA (x vs. y photon position, pre1:sector 10 problem, vertex z for pp06/pp08 data)
• November 2008
  1. 2008/11/25: Yields vs. analysis cuts: eta dependence
  2. 2008/11/21: Cluster Isolation cut from 2x1, 2x2, and 3x3 patch: rapidity dependence
  3. 2008/11/18: Isolation cut for 2x1, 2x2 and 3x3 tower clusters
  4. 2008/11/11: Yields vs. analysis cuts (event counter, data/MC ratio)
  5. 2008/11/06: Gamma-jet reconstruction with the Endcap EMC (Analysis status update for Spin PWG)
• October 2008
  1. 2008/10/30: SMD energy and shower shapes for various cuts: pt>8.5, Esmd>0.1, 8 vs. 12 strips replaced
  2. 2008/10/27: SMD-based shower shape scaling (25 strips cluster energy, raw vs. data-driven MC)
  3. 2008/10/21: Shower shapes, 5/25 strips cluster energy, raw vs. data-driven MC (with new filtered events)
  4. 2008/10/15: Purity/efficiency/rejection: R_cluster > 0.9 vs. 0.98 (update with gamma-filtered events)
  5. 2008/10/15: Gamma-jets from Michael's filtered events vs. old MC gamma-jet and QCD jets events
  6. 2008/10/14: Purity/efficiency/rejection: R_cluster > 0.98
  7. 2008/10/13: Jet and skim trees for Michael's gamma filtered events
• September 2008
  1. 2008/09/30: Sided residual: purity, efficiency, and background rejection
  2. 2008/09/23: Right-left SMD tail asymmetries
  3. 2008/09/23: Sided residual plot study
  4. 2008/09/23: QA plots for maximum sided residual (bug fixed update)
  5. 2008/09/16: QA plots for maximum sided residual (obsolete)
  6. 2008/09/09: Maximum sided residual from shower shapes sorted by uv- and pre-shower bins
  7. 2008/09/02: Shower shape's triple Gaussian fits
• August 2008
  1. 2008/08/27: Gamma-jet candidates detector position for different pre-shower conditions
  2. 2008/08/26: Shower shapes: more constrains for pre1>4E-3 bin (2D and projections for sided residual, pre1<10MeV cut)
  3. 2008/08/25: Di-jets QA from pp2008 vs. pp2006 data
  4. 2008/08/19: Shower shape from pp2008 vs pp2006 data
  5. 2008/08/14: Shower shape with bug fixed dd-library (raw shapes, pre1=4MeV cut, u/v shapes within 12 and 40 strips from peak)
• July 2008
  1. 2008/07/29: Shower shape comparison with new dd-library (pre1=4MeV cut, u/v shapes within 12 and 40 strips from peak)
  2. 2008/07/22: Photons from eta-meson: library QA (shower shapes [pre1=4E-3 cut], energy plots, etc)
  3. 2008/07/16: Gamma-gamma invariant mass cut study (inv mass, pt, shower shapes plots)
  4. 2008/07/07: Pre-shower1 < 5MeV cut study (shower shapes, pre1:pre2, pre1, pt, sided residual plots)
• June 2008
  1. 2008/06/18: Photon-jet reconstruction with the EEMC detector (Davis Collaboration Meeting)
  2. 2008/06/10: Longitudinal double spin asymmetry for gamma-jet candidates
  3. 2008/06/09: STAR White paper plots (pt distribution: R_cluster 0.99 and 0.9 cuts)
  4. 2008/06/04: 3x3 cluster energy in various EEMC layers (MC to data matching)
• May 2008
  1. 2008/05/30: Gamma and away side jet pt, eta and phi (MC to data matching)
  2. 2008/05/27: Shower shapes comparison (pp2006, MC gamma-jet, QCD jets, eta-meson gammas)
  3. 2008/05/21: Some eta-meson QA plots (invariant mass, detector eta, etc)
  4. 2008/05/20: Shower shapes (sorted by: pre-shower, z-vertex; gamma pt, eta, and phi)
  5. 2008/05/15: Vertex z distribution for gamma-jet candidates
  6. 2008/05/14: R_cluster>0.99 and pt matching (gamma and jet pt asymmetry)
  7. 2008/05/09: TPC tracking (detector eta 1<1.4)
  8. 2008/05/08: SMD high strips positioning (x:y and in-sector distributions)
  9. 2008/05/05: pt distributions and 1D-sided residual plots (data vs. MC g-jet and QCD jets)
• April 2008
  1. 2008/04/23: Sided residual and gamma:jet pt 2D plots (data driven MC vs. data)
  2. 2008/04/17: Sided residual (data driven vs. raw MC, pp2006) (plus: Geant vs. reconstructed pt, event counter)
  3. 2008/04/16: Sided residual (partonic pt 9-11) (plus: event counter)
  4. 2008/04/09: Reconstructing raw MC gamma-jet events (shapes, gamma:jet pt, phi, eta, sided residual, logD, chi2 plots)
  5. 2008/04/03: chi2-shape subtraction (request from Hal)
  6. 2008/04/02: Sided residual: 3 Gaussian fits and inv. mass sorting (plus: projections and signal/bg separation)
  7. 2008/04/02: Shower shapes: eta-meson and pp2006 vs. MC gamma-jets and single gammas
  8. 2008/04/02: Single gamma MC (sided residual plot)
• March 2008
  1. 2008/03/28: Shower shapes: pp2006 gamma-jets, MC (from Pibero), and eta-meson (plus: stip-by-strip energy, chi2 plots)
  2. 2008/03/26: Sided residual (2 Gaussian fits, with/without pt cuts) and chi2 (plus: pt, eta, phi, by-sector 2D plots)
  3. 2008/03/20: First look at sided residual and chi2 (plus: pdf-file with event-by-event EEMC response)
  4. 2008/03/12: M_2gamma invariant mass plots (plus: pdf-files with event-by-event EEMC response)
  5. 2008/03/03: EEMC SMD QA plots (mean energy for SMD high strips)
• February 2008
  1. 2008/02/27: EEMC vs. BEMC gamma-jet candidates (pt, eta, phi, 3x3 R_cluster vs. nTowers, various pt-cuts)
  2. 2008/02/20: NEF, pt, eta, phi for gamma-jet candidates (more statistics)
  3. 2008/02/13: Vertex z, m_2gamma inv. mass from simple pi0 finder (plus: pdf-files with event-by-event EEMC response)
• January 2008
  1. 2008/01/30: Gamma-jet candidates: numberOfJets/event, NEF, pt, eta, phi (first look, only runId=7136022)

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Selected figures

Figure 1:. Gamma candidate pt distributions for a three different data samples:

• pp2006 - STAR 2006 pp longitudinal data (~ 3.164 pb^1) after applying gamma-jet isolation cuts.
• gamma-jet - Pythia gamma-jet sample (~170K events). Partonic pt range 5-35 GeV.
• QCD jets - Pythia QCD jets sample (~4M events). Partonic pt range 3-65 GeV.

Note: Same algorithm has been used to analyse Monte-Carlo and real data events

Figure 2: Sided residual and sample gamma-jet candidate (EEMC response)