The STAR Dilepton Program

Slides:

Advertisements

Similar presentations

417 th WE-Heraeus-Seminar Characterization of the Quark Gluon Plasma with Heavy Quarks Physikzentrum Bad Honnef June 25-28, 2008 Ralf Averbeck, Heavy-Flavor.

Advertisements

Fukutaro Kajihara (CNS, University of Tokyo) for the PHENIX Collaboration Heavy Quark Measurements by Weak-Decayed Electrons at RHIC-PHENIX.

Charm & bottom RHIC Shingo Sakai Univ. of California, Los Angeles 1.

Di-electron Continuum at PHENIX Yorito Yamaguchi for the PHENIX collaboration CNS, University of Tokyo Rencontres de Moriond - QCD and High Energy Interactions.

Direct virtual photon production in Au+Au collision at 200 GeV at STAR Bingchu Huang for the STAR collaboration Brookhaven National Laboratory Aug

Bingchu Huang, USTC/BNL 1 Bingchu Huang (for STAR Collaboration) University of Science and Technology of China (USTC) Brookhaven National Laboratory (BNL)

1 Measurement of phi and Misaki Ouchida ｆ or the PHENIX Collaboration Hiroshima University What is expected? Hadron suppression C.S.R.

Cold Nuclear Matter Effects on Open Heavy Flavor at RHIC J. Matthew Durham for the PHENIX Collaboration Stony Brook University

4/1/2010MRPC workshop at USTC, Lijuan Ruan (BNL)1 STAR di-lepton measurements Outline: Motivation and Introduction Results from 200 GeV p+p collisions.

Non-photonic electron production in STAR A. G. Knospe Yale University 9 April 2008.

SQM2006, 03/27/2006Haibin Zhang1 Heavy Flavor Measurements at STAR Haibin Zhang Brookhaven National Laboratory for the STAR Collaboration.

Sourav Tarafdar Banaras Hindu University For the PHENIX Collaboration Hard Probes 2012 Measurement of electrons from Heavy Quarks at PHENIX.

Dilepton production in HIC at RHIC Energy Haojie Xu( 徐浩洁 ) In collaboration with H. Chen, X. Dong, Q. Wang Hadron2011, WeiHai Haojie Xu( 徐浩洁 )

1 The Study of D and B Meson Semi- leptonic Decay Contributions to the Non-photonic Electrons Xiaoyan Lin CCNU, China/UCLA for the STAR Collaboration 22.

Xiaoyan LinQuark Matter 2006, Shanghai, Nov , Study B and D Contributions to Non- photonic Electrons via Azimuthal Correlations between Non-

JSPS Research Fellow / University of Tsukuba T. Horaguchi Oct for HAWAII /10/15HAWAII

PHENIX Fig1. Phase diagram Subtracted background Subtracted background Red point : foreground Blue point : background Low-mass vector mesons (ω,ρ,φ) ～

Single Electron Measurements at RHIC-PHENIX T. Hachiya Hiroshima University For the PHENIX Collaboration.

Heavy flavor production at RHIC Yonsei Univ. Y. Kwon.

09/15/10Waye State University1 Elliptic Flow of Inclusive Photon Ahmed M. Hamed Midwest Critical Mass University of Toledo, Ohio October, 2005 Wayne.

Recent Charm Measurements through Hadronic Decay Channels with STAR at RHIC in 200 GeV Cu+Cu Collisions Stephen Baumgart for the STAR Collaboration, Yale.

Systematic measurement of light vector mesons at RHIC-PHNEIX Yoshihide Nakamiya Hiroshima University, Japan (for the PHENIX Collaboration) Quark Matter.

Measurements of thermal photons in heavy ion collisions with PHENIX - Torsten Dahms - Stony Brook University February 8 th, 2008 Real photons at low p.

03/13/2012Moriond QCD and High Energy Interactions, Mar Di-lepton production at STAR Outline: Motivation and Introduction Recent results from STAR.

M. Muniruzzaman University of California Riverside For PHENIX Collaboration Reconstruction of  Mesons in K + K - Channel for Au-Au Collisions at  s NN.

Ralf Averbeck Stony Brook University Hot Quarks 2004 Taos, New Mexico, July 19-24, 2004 for the Collaboration Open Heavy Flavor Measurements with PHENIX.

Dilepton Radiation Measured in PHENIX probing the Strongly Interacting Matter Created at RHIC Y. Akiba (RIKEN Nishina Center) for PHENIX Collaboration.

Non-photonic electron production in p+p collisions at √s=200 GeV Xiaozhi Bai for the STAR collaboration Central China Normal University University of Illinois.

Study of b quark contributions to non-photonic electron yields by azimuthal angular correlations between non-photonic electrons and hadrons Shingo Sakai.

JPS/DNPY. Akiba Single Electron Spectra from Au+Au collisions at RHIC Y. Akiba (KEK) for PHENIX Collaboration.

1 Guannan Xie Nuclear Modification Factor of D 0 Mesons in Au+Au Collisions at √s NN = 200 GeV Lawrence Berkeley National Laboratory University of Science.

X. DongAug , 2014 TPD RBRC Workshop, BNL Dielectron Mass Spectrum & Elliptic Flow at Au+Au 200 GeV Xin Dong Lawrence Berkeley National Laboratory.

Resonance Workshop -- 3/7/2012 Sarah Campbell for the PHENIX Collaboration Resonance Workshop 2012 March 6, 2012 Austin, TX Light Vector Mesons and the.

Outline Motivation The STAR/EMC detector Analysis procedure Results Final remarks.

24 Nov 2006 Kentaro MIKI University of Tsukuba “electron / photon flow” Elliptic flow measurement of direct photon in √s NN =200GeV Au+Au collisions at.

Hadronic resonance production in Pb+Pb collisions from the ALICE experiment Anders Knospe on behalf of the ALICE Collaboration The University of Texas.

Christina MarkertHirschegg, Jan 16-22, Resonance Production in Heavy Ion Collisions Christina Markert, Kent State University Resonances in Medium.

05/23/14Lijuan Ruan (BNL), Quark Matter The low and intermediate mass dilepton and photon results Outline: Introduction New results on dileptons.

Systematic measurement of light vector mesons at RHIC-PHNEIX Yoshihide Nakamiya Hiroshima University, Japan (for the PHENIX Collaboration) Quark Matter.

Elliptic Flow of Inclusive Photon Elliptic Flow of Inclusive Photon Ahmed M. Hamed Midwest Critical Mass University of Toledo, Ohio Oct. 22,

J. Zhao Hard Probe 2012, Cagliari 1, Lawrence Berkeley National Lab, USA 2, Shanghai Institution of Applied Physics, CAS, China Di-electron Production.

Dileptons: Penetrating probes at all time scales Very low cross-section with QCD medium Window into all stages of system evolution Chronological hierarchy.

Non-Prompt J/ψ Measurements at STAR Zaochen Ye for the STAR Collaboration University of Illinois at Chicago The STAR Collaboration:

Fall DNP Meeting,  meson production in Au-Au and d-Au collision at \ /s NN = 200 GeV Dipali Pal Vanderbilt University (for the PHENIX collaboration)

Di-electron elliptic flow in

Ilia Ravinovich for the PHENIX Collaboration

Richard Petti For the PHENIX Collaboration

25 Years of Dilepton Experiments

Day of Femtoscopy 2016, Gyöngyös

Resonance and low-mass vector meson production in ALICE

High-pT Identified Hadron Production in Au+Au and Cu+Cu Collisions

Tatia Engelmore, Columbia University

Dileptons and Photons at RHIC Energies

STAR Geometry and Detectors

Sarah Campbell For the PHENIX Collaboration

Quarkonium production in ALICE

Open heavy flavor analysis with the ALICE experiment at LHC

Charm production at STAR

Elliptic Flow in PHENIX

Tatsuya Chujo University of Tsukuba (for the PHENIX Collaboration)

The Study of Elliptic Flow for PID Hadron at RHIC-PHENIX

Scaling Properties of Identified Hadron Transverse Momentum Spectra

20th International Conference on Nucleus Nucleus Collisions

High-pT Identified Charged Hadrons in √sNN = 200 GeV Au+Au Collisions

Hiroshi Masui for the PHENIX collaboration August 5, 2005

Identified Charged Hadron Production at High pT

Shingo Sakai for PHENIX Collaborations (Univ. of Tsukuba)

Shingo Sakai for PHENIX Collaborations (Univ. of Tsukuba)

Systematic measurements of light vector mesons in RHIC-PHENIX

Masahiro Konno (Univ. of Tsukuba) for the PHENIX　Collaboration Contact

Presentation transcript:

The STAR Dilepton Program Frank Geurts (Rice University) for the STAR Collaboration

Quark Matter 2012 -- Washington D.C. Outline Introduction & Motivation Electron Identification in STAR Dielectron Production at √sNN= 200 GeV p+p and Au+Au results elliptic flow of dielectrons Results from Beam Energy Scan Program STAR Dilepton Present & Future Summary 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Quark Matter 2012 -- Washington D.C. Dilepton Physics Dileptons are excellent penetrating probes very low cross-section with QCD medium created throughout evolution of system Chronological division: High Mass Range (HMR) Mee > 3 GeV/c2 primordial emission, Drell-Yan J/Ψ and ϒ suppression Intermediate Mass Range (IMR) 1.1 < Mee< 3 GeV/c2 QGP thermal radiation heavy-flavor modification Low Mass Range (LMR) Mee< 1.1 GeV/c2 in-medium modification of vector mesons possible link to chiral symmetry restoration 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Dilepton Elliptic Flow Elliptic flow is generated very early stage dileptons can further probe this early stage possibly constrain QGP EoS Combination of pT and Mll can set observational windows on specific stages of the expansion Chatterjee et al., Phys Rev. C 75 (2007) 054909 Expect interesting structures in pT-integrated v2(M): high-mass dileptons hot early stage flow is still weak low-mass dileptons flow strong, temperature low modulations from the contributions of vector mesons strong variations of relative weights on/off resonances 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Quark Matter 2012 -- Washington D.C. The STAR Detector Large acceptance electron ID Time Projection Chamber Time-of-Flight detector 2009: 72% completed (p+p) 2010: fully commissioned Electromagnetic Calorimeter Poster: K. Jung (125) TOF cut removes “slow” hadrons improves electron purity central events ~92% min-bias events ~95% Time Projection Chamber 0<ϕ<2π, |η|<1 Tracking dE/dx PID Time-of-Flight Detector 0<ϕ<2π, |η|<0.9 Time resolution < 100ps Significantly improves PID 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

e+e- Invariant Mass & Background Background sources combinatorial background (non-physical) correlated background e.g. double Dalitz decay, jet correlation. Background methods mixed-event method: combinatorial only improve statistics like-sign method: combinatorial & correlated BG correct for acceptance differences pair cuts remove photon conversions Other signals (meson decays) Remove by comparing real data with simulations for hadron contamination Hadron Simulation Cocktail Combine both methods: p+p: LS < 0.4 GeV/c2 < ME Au+Au: LS < 0.75 GeV/c2 < ME×LS carefully normalized using overlap in Mee S/B @ Mee~ 0.5 GeV/c2: 1/10 for p+p 1/250 for Au+Au central 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Production in p+p at 200 GeV Phys. Rev. C 86, 024906 (2012) Understand the p+p reference Cocktail simulation consistent with data L. Ruan (STAR), Nucl. Phys. A855 (2011) 269 Charm contribution dominates IMR scaled with STAR charm cross-section Adams et al (STAR), Phys. Rev. Lett. 94 (2005) 062301 Uncertainties: vertical bars: statistical boxes: systematic grey band: cocktail simulation systematic not shown: 11% normalization 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Production in Au+Au at 200 GeV Low Mass: enhancement when compared to cocktail (w/o ρ meson) little centrality dependence Intermediate Mass: cocktail “overshoots” data in central collisions but, consistent within errors modification of charm? STAR Preliminary STAR Preliminary difficult to disentangle (modified) charm from thermal QGP contributions future detector upgrades required B. Huang (3C, 268) Poster: Y. Guo (153) H. Huang (6C - 142) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Compare to Rapp, Wambach, v. Hees STAR central 200 GeV Au+Au hadronic cocktail (STAR) Ralf Rapp (priv. comm.) R. Rapp, Phys.Rev. C 63 (2001) 054907 R. Rapp & J. Wambach, EPJ A 6 (1999) 415 Complete evolution (QGP+HG) cocktail + HG + QGP: Agreement w/in uncertainties hadronic phase: ρ “melts” when extrapolated close to phase transition boundary total baryon density plays the essential role top-down extrapolated QGP rate closely coincides with bottom-up extrapolated hadronic rates Rapp, Wambach, van Hees arXiv:0901.3289 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Compare to Theory: PHSD Model Parton-Hadron String-Dynamics O. Linnyk et al., Phys. Rev. C 85 024910 (2012) H. Xu et al., Phys. Rev. C 85 024906 (2012) Collisional broadening of vector mesons Radiation from QGP Minimum bias collisions (0-80%): Generally good agreement Central collisions (0-10%): PHSD roughly in line with LMR region 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Elliptic Flow in Au+Au at 200 GeV First measurements from STAR 700M min-bias events combined 2010/2011 Background: Like-Sign Mee<0.7 GeV/c2 Mixed-Event Mee>0.7 GeV/c2 Event-Plane method: TPC Cocktail contributions: dielectron v2(Mee): data and simulations consistent work in progress to include IMR v2 Poster: X. Cui (322) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Dielectron v2 pT Dependence Poster: X. Cui (322) Comparison with measured v2(pT) π± (STAR) and π0 (PHENIX) Mee < 0.14 GeV/c2 φ K+K- (STAR) 0.98 < Mee < 1.06 GeV/c2 Au+Au √sNN= 200GeV 0-80% centrality PHENIX, PRC 80 (2009) 054907 v2(pT) consistent with simulations & measurements 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Dielectron v2 Centrality Dependence Centrality dependence v2(pT) Mee<0.14 GeV/c2 consistent with simulations consistent with measurements Can we distinguish between HG and QGP v2 contributions? Recall: need uncertainties to be <4% (compared with model differences) … Require ~2x more Au+Au min-bias data and e-μ measurements at higher Mee to disentangle charm contributions no, not yet. 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Dielectron Production at lower √sNN Observed Low-Mass enhancement at top RHIC energy in-medium modification effects? indication of chiral symmetry restoration? Explore Low Mass Range down to SPS energies possible enhancement, consistent model description? Beam Energy Scan Dielectrons: 2010 - 2011 Au+Au at 62.4, 39, and 19.6 GeV STAR data samples: 55M, 99M, and 34M min-bias events Posters: P. Huck (113), B. Huang (269) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Comparison to SPS measurements STAR Au+Au at 19.6 GeV/c min-bias (0 - 80%) pT>0.2GeV/c, |η|<1, |yee|<1 Cocktail: π0 yield: STAR π± other mesons: NA49-based, scaled with SPS meson/π0 ratio CERES Pb+Au at 17.2 GeV/c CERES, Eur.Phys.J. C 41 (2005) 475 semi-central (0-28%) pT>0.2GeV/c, 2.1<η<2.65, θee>35mrad STAR Preliminary STAR enhancement comparable to CERES … and with better mass resolution Posters: B. Huang (269) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Compare to Theory: in-medium ρ Robust theoretical description top RHIC down to SPS energies calculations by Ralf Rapp (priv. comm.) black curve: cocktail + in-medium ρ Measurements consistent with in-medium ρ broadening expected to depend on total baryon density tool to look for chiral symmetry restoration STAR Preliminary 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

STAR Dileptons: Present & Future 2009 – 2011 TPC + TOF + EMC dielectron continuum dielectron spectra, and v2 (pT) vector meson in-medium modifications LMR enhancement modification in IMR? 2012-2013 TPC + TOF + EMC + MTD (partial) e-μ measurements IMR: Improve our understanding of thermal QGP radiation LMR: vector meson in-medium modifications 2014 and beyond TPC + TOF + EMC + MTD + HFT dimuon continuum e-μ spectra and v2 LMR: vector meson in-medium modifications IMR: measure thermal QGP radiation More on HMR physics: Wei Xi – Heavy Flavor Results from STAR (Plenary IIB) More on MTD and HFT: Huan Huang – STAR Upgrade Plan for the Coming Decade (Parallel 6C) Poster: C. Yang (331) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Quark Matter 2012 -- Washington D.C. Summary STAR detector very well suited for dilepton physics recent TOF upgrade allows for large acceptance electron ID Dielectron in p+p and Au+Au at √sNN=200 GeV: centrality and pT differentials observe low mass enhancement Dielectron elliptic flow measurements in Au+Au at √sNN=200 GeV v2(Mee,pT) results consistent with other measurements & cocktail simulations need ~2x increase in statistics to distinguish HG and QGP contributions Dielectron measurements in Au+Au at √sNN= 19.6 – 62.4 GeV low mass enhancement down to SPS energies, with comparable magnitude consistent with in-medium ρ broadening robust and consistent description for √sNN= 19.6, 62.4, and 200 GeV Future STAR upgrades enable further exploration of the dilepton continuum upcoming MTD upgrade allows for large acceptance μ ID QGP thermal radiation measurements 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

STAR Dilepton Presentations at QM’12 B. Huang – parallel session 3C (268) Di-electron differential cross section in Au+Au collisions at different beam energies at STAR X. Cui – poster 322 Centrality, mass and transverse momentum dependence of di-electron elliptic flow in √sNN = 200 GeV Au+Au collisions at STAR K. Jung – poster 125 A Study of High-pT/High-mass Dielectron Production through Trigger Combination in 200 GeV Au+Au Collisions at STAR B. Huang – poster 269 Low mass di-electron production in Au+Au collisions at √sNN = 19.6 GeV at STAR P. Huck – poster 113 Dielectron Production in Au+Au-Collisions √sNN= 39 & 62.4 GeV at STAR M. Wada – poster 110 ω(782) and φ (1020) mesons from di-leptonic decay channels at the STAR experiment Y. Guo – poster 153 Centrality and pT dependence study of Dielectron Production √sNN = 200 GeV Au+Au collisions at STAR H. Huang – parallel session 6C (142) STAR Upgrade Plan for the Coming Decade C. Yang – poster 331 Performance of the Muon Telescope Detector in STAR at RHIC 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Quark Matter 2012 -- Washington D.C. BACKUP 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Hadronic Background Simulation Au+Au 200GeV Au+Au 39 & 62GeV Au+Au 19.6 GeV STAR Preliminary STAR Preliminary TBW fit from NA49 data π yield from STAR Extrapolated from AMPT calculations. Scaled to measurements at 200GeV p+p 200GeV Hadrons: flat |y|<1.0, and flat full azimuthal input distribution pT distribution from Tsallis blast-wave fit to measured particle spectra Heavy flavor sources: STAR measurements, and PYTHIA simulation Nbin scaled in Au-Au at low energy: FONLL STAR Preliminary 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Dielectron Mee for 39 and 62GeV STAR Preliminary STAR Preliminary Poster: P. Huck (113) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Systematic Uncertainties p+p@200GeV Background subtraction 0 - 27% hadron contamination 0 - 32% efficiency ~10% total normalization ~11% cocktail simulation 14 - 33% Au+Au@200GeV STAR Preliminary Au+Au@19.6GeV Tracking efficiency 7% TOF matching 5% Pair uncertainties (summed) 17% cocktail uncertainties 12-20% 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Leptonic Decay of φ and ω Mesons Lifetimes comparable to fireball hadronic decay daughters interact with hadronic medium sensitive to lifetime of that medium leptonic decay daughters do not interact with QCD medium look for medium modifications to resonance mass & width sensitive to chiral phase transition small branching ratio No evidence of φ mass shift or width broadening beyond known detector effects φ yield in dilepton decay channel consistent with hadronic channel ω pT shapes agree with light hadrons ω mass and width are under study Poster: M. Wada (110) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

PHENIX & STAR Enhancement Factor QM/SQM2011 Enhancement factor in 0.15<Mee<0.75 Gev/c2 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Dielectron Enhancement vs. √sNN Systematic measurements of enhancement factor vs. √sNN STAR data shows no evident beam-energy dependence 150-750 MeV/c2 range low energy: comparable with CERES high energy: discrepancy with PHENIX 200 < Mee < 600 MeV/c2 range STAR: 1.9 ± 0.6 ± 0.4 CERES: 2.73 ± 0.25 ± 0.65 ± 0.82 [decays] B. Huang (3C, 268) Poster: P. Huck (113) 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

Reproducing the PHENIX Cocktail STAR preliminary Reproduce the cocktail within PHENIX acceptance by our method. The momentum resolutions are still from STAR. SQM2011 Scaled by all the yields from PHENIX paper[1], STAR reproduces the PHENIX cocktail. [1]. Phys. Rev. C 81, 034911 (2010). 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.

STAR with PHENIX Acceptance 12 sectors east and west barrel 2π coverage, |η|<1 PHENIX 20 sectors east and west arm π coverage, |η|<0.35 Hard Probe 2012 8/16/12 -- Frank Geurts Quark Matter 2012 -- Washington D.C.