- Spin Structure of Proton - Properties of QCD Matter at Extreme Conditions - QCD Phase Structure

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1 STAR Physics Program - Spin Structure of Proton - Properties of QCD Matter at Extreme Conditions - QCD Phase Structure Nu Xu (1) Nuclear Science Division, Lawrence Berkeley National Laboratory Berkeley, USA (2) College of Physical Science and Technology, Central China Normal University Wuhan, China 1/15

2 STAR Experiment STAR Experiment at RHIC ( ) Fundamental science: particle physics, nuclear physics, astrophysics, cosmology, State of art technology: detector R&D, simulations, IT, computing, mass/fast data managing, scientists - 55 institutes - 13 countries PhD thesis since 2001 Nu Xu STAR Regional Meeting, ShanDong University, Jinan,, 22 23, October, /15

3 STAR Physics Focus 1) At 200 GeV top energy - Study medium properties, EoS - pqcd in hot and dense medium 2) RHIC beam energy scan (BES) - Search for the QCD critical point - Chiral symmetry restoration Forward program - Study low-x properties, initial condition, search for CGC - Study elastic and inelastic processes in pp2pp Polarized p+p program - Study proton intrinsic properties 3/15

4 STAR Detectors Fast and Full azimuthal particle identification TPC TOF EMC+EEMC+FMS (-1 η 4) DAQ1000 HFT 2013 FGT BNL PAC, 21-22, MTD 2013 Nu Xu STAR Regional Meeting, ShanDong University, Jinan,, 22 23, October, /15

5 Particle Identification at STAR TPC ToF TPC STAR TPC K p d π e, µ STAR MTD STAR ToF Log 10 (p) STAR HFT STAR EMC Neutral particles Strange Jets Heavy Quark hyperons Hadrons Multiple-fold correlations among the identified particles! 5/15

6 TOF Performance (2010) s NN = 39 GeV Au + Au Collisions TPC TPC+ToF 2 Au+Au 39 GeV /! p*q (GeV/c) 1 Beam Energy Timing Resolution Remarks 200 (GeV) 85 (ps) At 39 GeV, using a new calibration 62.4 (GeV) 90 (ps) scheme without information of start time from VPD, 87 ps of timing resolution 39 (GeV) 85 (ps) has been achieved & 7.7 (GeV) ~ 80 (ps) 6/15

7 STAR Upgrade Timeline* Upgrade Completion Key Physics Measurements FMS Completed 2008 *Upgrades - Funding driven schedules (a) Trans. Asymmetry at forward-y (b) CGC TPC DAQ1000 Completed 2009 Minimal dead time, large data set MRPC TOF Completed 2010 Fast PID in full azimuthal acceptance Forward GEM Tracker Heavy Flavor Tracker Muon Telescope Detector pp2pp Summer 2011 Ready for Run 12 Summer 2013 Ready for Run 14 Summer 2013 Ready for Run 14 Summer 2014 Ready for Run 15 Forward-y W ± for flavor separated quark polarization (a) Precision hadronic ID for charm and Bottom hadrons (b) Charm and Bottom hadron energy loss and flow (a) High p T muon trigger (b) Quarkonia states 7/15

8 Forward GEM Tracker (2011) HFT FGT 1) FGT: RHIC CE project 2) Six light-weight triple-gem disks 3) New mechanical support structure 4) Planned installation: Summer ) Full charge-sign discrimination at highpt 2) Design polarization performance of 70% to collect at least 300pb -1 8/15

9 Heavy Flavor Tracker (2014) SSD HFT IST PXL FGT 1) Identify heavy flavor hadron directly 2) Precision measurement HF hadron energy loss and collectivity 9/15

10 HFT: Charm Hadron v 2 and R AA GeV Au+Au m.b. collisions (500M events). - Charm hadron collectivity drag/diffusion constants - Medium properties! - Light quark thermalization! GeV Au+Au m.b. collisions ( y < M events) - Charm hadron R AA - Energy loss mechanism! - QCD in dense medium! 10/15

11 Muon Telescope Detector (2013) beam pipe TPC TOF EMC magnet MTD Muon Telescope Detector (MTD) at STAR: 1) MRPC technology; µε ~ 45%; cover ~60% azimuthally and y < ) TPC+TOF+MTD: muon/hadron enhancement factor ~ ) For high pt muon trigger, heavy quarkonia, light vector mesons, B J/Ψ+X 4) China-India-STAR collaboration: a proposal sub. to BNL 02/2010. Nu Xu STAR Regional Meeting, ShanDong University, Jinan,, 22 23, October, /15

12 Summary STAR QCD physics program for next decade: Spin Physics: (cold nucleon) GeV: Δg inclusive and di-jets, γ-jet GeV: sea quark helicity distributions - 200/500 GeV: transverse spin phenomena Low-x Physics: (cold nucleus) - Study gluon-rich phenomena at RHIC - Color glass condensate Heavy Ion Physics: (hot nuclear matter) - Thermalization at s NN = 200 GeV - QCD phase boundary and critical point - In medium properties 12/15

13 Decadal Plan see Carl s talk Decadal Plan C. Gargliardi Spin B. Surrow Heavy Ion J. Dunlop Upgrade F. Videbaek Charge for new decadal plans for STAR and PHENIX by Steve Vigdor, Dec. 17, due date: Oct. 1, /15

14 erhic Design erhic detector 2 SRF linac 1 -> 5 GeV per pass 4 (6) passes RHIC: 325 GeV p or 130 GeV/u Au with DX magnets removed estar S. Vigdor: 2010 Operation review

15 STAR Experiment MTD EMC Barrel EMC End Cap BBC FMS FHC FPD TPC pp2pp pp2pp PMD trigger computing COMPLETE HLT HFT FGT Ongoing R&D 15/15

16 Few Remarks 1) Reports on STAR status: - physics Spin and HI - upgrades 2) Theoretical discussions: - lots of interesting theoretical issues. - Fundamental understanding of nucleon structure - EIC (erhic at BNL) and p-pbar collider are needed for further understanding the nucleon spin structure (PANDA at FAiR). 3) Future activities: - more students from SDU and PKU will join STAR analysis. - in18 month, in spring of 2012, we will have STAR Spin Regional Meeting at SDU. Many Thanks to the Organizers: Qinghua, Zuotang and SDU team! 16/15

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