1. EMCal PPR Group 4 – Electrons/Heavy Flavor-Jets
Coordinators: J.Klay (Calpoly), K.Read (Tennessee), M. Heinz (Yale)
Group Members:
Josh Hamblen & Irakli Martashvili (Tennessee)
Udara Abeysekara (Creighton)
Alberto Lozea (USP-Sao Paolo)
Brandon Boswell & Christopher Brown (Cal Poly)
Per Thomas Hille & Student (Yale)
Mauro Cosentino (Campinas)
Weekly EVO meetings organized by Ken: Thursdays 11:00am EDT
C.) Electron and heavy flavor jet reconstruction
Electron reconstruction
Electron-jet reconstruction
Heavy quark energy loss
Heavy quark fragmentation functions

2. Heavy quark tagging with electrons
Show electron to heavy meson correspondence in AA collisions.
Optimize e/h discrimination
Simulate signed DCA method for B-mesons
Direct reconstruction of high pT J/

3. Issues and Updates Electron dE/dx cut AliEn/GRID Software
Track-matching bug
PWG4
B-jet simulations
Plans

4. Electron ID with dE/dx cut
Joern suggested at LBL meeting to look at dE/dx cut for matched tracks when identifying electrons (a la STAR)
dE/dx > 70
Single e: All matched tracks
PYTHIA: All matched tracks
Single e: MC PDG = e
PYTHIA: MC PDG = e

5. AliEn/GRID Since April LBL Meeting
We learned that GRID productions unusable
Committed new track-matching parameters
Continued testing software for running large-scale jobs on grid
Current Status
Migrated to PWG4 and ALICE Analysis framework
Ken Read put together completely working, documented example at /afs/cern.ch/users/k/kread/public/all
Ready to validate productions

6. Track-matching bug
Committed new track-matching parameters after LBL meeting
Subsequent testing indicated a problem
All matches marked as “fake” during reconstruction, thus no matched tracks assigned to clusters
“Fake” means MC label of track != MC label of cluster
Two different methods for matching exist
AliESDtrack + AliESDCaloCluster (post-reconstruction)
AliESDtrack + AliEMCALRecPoint (during reconstruction)
AliEMCALRecPoint->GetPrimaryIndex() was being used to get the MC label, but should have been AliEMCALRecPoint->GetParents()
Bug report and fix submitted to savannah (14-May-09) and patched to release by P. Hristov (15-May-09)

7. PWG4 Analysis Code
As of 14-May-09 all PPR Group 4 members agreed to migrate to PWG4 analysis framework
Adheres to ALICE analysis framework
Provides much of functionality needed without duplicated effort
Cross-section weighting
JetFinder correlation integration
Interface to various data types
Example AliAnalysisTaskElectron provided to group members (JLK)
Ken Read adapted example to run in any of 5 modes:
Local, LocalCAF, PROOF, GRID, PLUGIN
Code tested, documented and available to everyone
/afs/cern.ch/users/k/kread/public/all

8. B-Jet Simulations
Recently discovered requested update to AliGenPythia (Oct-08) was not included
Previous electron-jet GRID productions not optimized
Missing information
In order to correlate MC and reconstruction, need to save MC jet info (previously only done for Jet-Jet, -Jet)
Incorrect configuration
No call to check trigger conditions of requested b-jets
In order to improve efficiency, need to require electron with minimum pT in fiducial volume of EMCAL
Bug report and fixes submitted (14-May-09) with request for review
A. Morsch reviewed fix and responded to add process definition to AliPythia
Testing in progress, final fixes imminent

9. Examples
50 > pThard > 60
pT(e) > 1 GeV in EMCAL

10. Examples
50 > pThard > 60
pT(e) > 1 GeV in EMCAL

11. Activities Matrix – group 4
Task
Sub-topics/ Physics
Plots
Manpower 1
Revisit rates
(higher stats)
1.1) Electron rates and backgrounds
1.2) B-jet rates and backgrounds
1.3) Hadron rejection requirement
E-rates from different sources
B-jet rates for electron selection
Hadron/electron ratio
Jenn 2
Re-check e-ID
2.1) Track-matching in PYTHIA/HIJING
2.2) p/E cut study
2.3)  rejection vs. pT for given efficiency levels
Matching efficiency + Fakes
p/E example distributions
Rejection vs. efficiency
Josh 3
Spectra/RAA (single electrons)
3.1) Investigate heavy flavor production via non-photonic electron measurement – Cross-check with NLO predictions
3.2) Investigate HF suppression in heavy ion collisions via R_AA (parton suppression)
Electron Spectra in p-p Collisions for PID with: (1) TPC, (2) TPC+TRD, (3) TPC+TRD+EMCAL
Electron Spectra in Pb-Pb (Hijing) Collisions for PID with: (1) TPC, (2) TPC+TRD, (3) TPC+TRD+EMCAL
Inclusive electrons vs non-photonic electrons
Irakli + Ken
Task
Sub-topics/ Physics
Plots
Manpower 4
B-jets
5.1) Event-by-Event B-tagging (using Jet-Finder + Displaced Vertex Method (DVM))
5.2) Event-by-Event B-tagging (using Jet-Finder + Transverse IP significance)
5.3) Measurement of B-jet Fragmentation function (statistical using Jet-Finder + tagging algorithm)
B-jet efficiency and false identification rate vs. pT for DVM, other tag methods
Rejection rates for non-B-jet vs. pT for DVM, other tag methods
B-jet Fragmentation Function sensitivity for various Jet-reco algorithms in p+p
5.1) Jenn, Brandon, Chris
5.2) Alberto & Mauro
5.3) Yale,
Udara

12. Plans Added task to matrix: J/  ee in EMCAL (Mauro Cosentino)
Continue developing code within PWG4 framework
Working with HFE (heavy flavor electron) group led by Silvia Masciocchi from PWG3 to make sure we coordinate effort/don’t duplicate work
Analyze grid data when available
Produce final PPR plots