TAR Non-photonic electron yields in p+p collisions at 200 Gev with reduced detector material in Star > Introduction and motivation Electron identification Photonic background Current status and future plan Summary 2008 F Jin for star collaboration Shanghai Institute of Applied Physics, CAS BROOKHAUEN NATIONAL LABORATORY e Jin
-------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------- F. Jin Non-photonic electron yields in p+p collisions at 200 GeV with reduced detector material in STAR ➢ Introduction and motivation ➢ Electron identification ➢ Photonic background ➢ Current status and future plan ➢ Summary F. Jin for STAR Collaboration Shanghai Institute of Applied Physics, CAS 1
TAR Introduction and motivation Open charm K Total charm cross section 1)test perturbative QCd prediction 2)input the cross section to do model calculation -Radial and elliptic flow d)bulk Qcd medium properties density, the drag coefficient and viscosity 2)test light flavor thermalization -Energy loss D K T e Jin
-------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------- F. Jin 2 Open charm –Total charm cross section 1) test perturbative QCD prediction 2) input the cross section to do model calculation –Radial and elliptic flow 1) bulk QCD medium properties ( density, the drag coefficient and viscosity ) 2) test light flavor thermalization –Energy loss Introduction and Motivation
TAR Current status of charm measurement STAR (nucl-ex/0607012 400F STAR Preliminary O STAR D+H+e(Au+Au) STAR(PRL 94(2005)062301). exP/GFONLL STAR D+e(d+Au) 口 STAR D(Cu+Cu) PHENIX (hep-ex/0609010) △ PHENIX e(Au+Au) HENIX e(p+p) PHENIXμ(p+p) 3200 8 sys. error Color dipole 100 HSD PYTHIA 回图 Rapidity y STAR: Larger acceptance PhEnIX. Lower material STAR removed svt and ssd in run 8, low material (0.55%Xo) run to try to address the observed 0246810 discrepancy between STAR and p(EviC PHENIX e Jin
-------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------- F. Jin 3 STAR: Larger acceptance PHENIX: Lower material STAR removed SVT and SSD in run 8, low material (~0.55%X0 ) run to try to address the observed discrepancy between STAR and PHENIX. Current status of charm measurement
TAR STAR-TOF STAR Detector Data sam ple in Run vil: 口 5 trays out of 120 trays lme t Coverage:-1<n0,△<兀/6 Set behind the tpx sector (TPC with upgraded I eran Time fre jee tlen CM electronics DAQ1000) x2/ndf 729.1|65 Constant 3984±14.3 78 M TOF triggered events Mean0.007447±0.000315 0.1102±0.0003 equivalent to 400 M minimum bias events 2500 TOF system timing resolution: 110 ps I)start time resolution -83ps 2)TOF intrinsic time resolution -75ps Efficiency: >90% TOF-TOF. e Jin
-------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------- F. Jin 4 ➢ 5 trays out of 120 trays ➢ Coverage: -1<<0, </6 ➢ Set behind the TPX sector (TPC with upgraded electronics DAQ1000) ➢ 78 M TOF triggered events, equivalent to ~400 M minimum bias events Data sample in Run VIII: TOF system timing resolution: ~110 ps 1) start time resolution ~83ps 2) TOF intrinsic time resolution ~75ps Efficiency: >90% STAR-TOF
TAR Event and track selection 1) Ensure good TOF hits delta Y <1.5(cm) 2)TOF acceptance 1<n<0 150 Ensure rapidity distribution o 100 electron similar as that of pion 0.6<y<0 4)Ensure good primary track VAVPD)-VA(TPC)K<6( cm) .100 E 0900 50100150200 Vz from VPD (cm) e Jin
-------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------- F. Jin 5 1) Ensure good TOF hits |deltaY|<1.5(cm) 2) TOF acceptance 10 3) Ensure rapidity distribution of electron similar as that of pion 0.6<y<0 4) Ensure good primary track | Vz(VPD) – Vz(TPC) |<6(cm) Event and track selection