1 / 28

马余刚 On behalf of China-STAR Group Shanghai Institute of Applied Physics (SINAP)

RHIC-STAR 中国组物理研究进展. 马余刚 On behalf of China-STAR Group Shanghai Institute of Applied Physics (SINAP) Central China Normal University, Wuhan (CCNU) University of Science and Technology of China (USTC) Tsinghua University (TU) Institute of Modern Physics, Lanzhou (IMP)

aysel
Download Presentation

马余刚 On behalf of China-STAR Group Shanghai Institute of Applied Physics (SINAP)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. RHIC-STAR中国组物理研究进展 马余刚 On behalf of China-STAR Group Shanghai Institute of Applied Physics (SINAP) Central China Normal University, Wuhan (CCNU) University of Science and Technology of China (USTC) Tsinghua University (TU) Institute of Modern Physics, Lanzhou (IMP) Institute of High Energy Physics, Beijing (IHEP) Shandong University(SDU) 十三届全国中高能核物理大会 暨第七届全国中高能核物理专题研讨会 合肥，11月 5-7号，2009

  2. About STAR-China group & previous physics results based on the TOF trays and STAR detectors; Recent progress: Discovery of anti-hypertriton V2 scaling & violation, thermalization Strangeness Heavy flavor and Eloss Energy scan and critical point search Longitudinal spin transfer Summary & Outlook 报告内容

  3. Whathave we learned? STAR NPA 757 (2005) 102 Strongly interacting, hot, dense matter with partonic collectivity What do we do next? Investigate the medium properties: - thermalization degree / EoS - search for chiral symmetry restoration Search for QCD critical point and phase boundary … N. Xu

  4. The STAR Detector - 2 Coverage at Midrapidity

  5. Typical PID for TPC-alone and TOF alone TPC alone TOF “alone” p k  TOF=110ps TPC alone PID range: pi/k ~0.6 GeV/c, (pi,k)/p ~1.6GeV/c; TOF “alone” PID range: pi/k ~1.6GeV/c, (pi,k)/p ~ 3.0GeV/c m2 m2

  6. 2007 2008 2006 STAR 1/2 3/4 5/6 7/8 11/12 1/2 3/4 5/6 7/8 1/2 3/4 5/6 7/8 11/12 9/10 9/10 Prod Start 132 MRPCs 768 MRPCs 1856 MRPCs 2944 MRPCs 4032 MRPCs Plan MRPC mass production (Finished) Scope of joint effort supported by NNSFC, CAS and MoST: Six institutions in China are collaborating on the STAR physics program, and on the construction of a 23,000 channel multi-gap resistive plate chamber Time of Flight barrel for STAR Group Leaders for China-TOF project: Yu-Gang Ma (SINAP); Hong-Fang Chen (USTC); Jian-Ping Cheng (Tsinghua) Project Scope:$4.7M from US $2.3M from China (in-kind) University of Science and Technology of China (USTC) Tsinghua University Shanghai Institute of Applied Physics (SINAP) Central China Normal University (CCNU) Institute of Modern Physics (IMP) Institute of High Energy Physics (IHEP) STAR TOF MRPC modules: production completed in China on schedule! 所有MRPC探测器都已在STAR上安装，可以马上采集相关数据！！

  7. Open Charm Yields in d +Au Collisions at sNN p 200 GeV, Phys. Rev. Lett. 94, 062301 (2005) Identified baryon and meson distributions at large transverse momenta from Au+Au collisions at sqrt(sNN)=200 , Phys. Rev. Lett. 97, 152301 (2006) Partonic flow and -meson production in Au+Au collisions at √sNN = 200 GeV，Phys. Rev. Lett. 99 (2007) 112301 Pion, kaon, proton and anti-proton transverse momentum distributions from p +p and d +Au collisions at √sNN = 200 GeV, Phys. Lett. B 616 (2005) 8 Energy and system size dependence of meson production in Cu+Cu and Au+Au collisions, Phys. Lett. B 673 (2009) 183 Spin alignment of K*0(892) and phi(1020) mesons in Au+Au and p+p collisions at sqrt(s_NN) = 200 GeV, Phys. Rev. C 77 (2008) 061902 (R) Mass, quark-number, and √sNN dependence of the second and fourth flow harmonics in ultrarelativistic nucleus-nucleus collisions，Phys. Rev. C 75 (2007) 054906 Centrality dependence of charged hadron and strange hadron elliptic flow from √sNN = 200 GeV Au+Au collisions, Phys. Rev. C 77, 054901 (2008) Measurements of phi meson production in relativistic heavy ion collisions at RHIC, Phys. Rev. C 79, 064903 (2009) J/ψ production at high transverse momenta in p + p and Cu + Cu collisions at √sNN = 200 GeV, Phys. Rev. C 80, 041902(R) (2009) Distinguished PhD Students: 中国合作组有许多优秀的学生，例如： 付菁华（华中），2005年度“全国百篇优秀博士论文”奖； 马国亮（上海应物所）, 张一飞(中科大)获得了2006,2007年度“中国科学院院长奖学金优秀奖”； 陈金辉（上海应物所）2008年度“中国科学院院长奖学金优秀奖”和“2009年中科院50篇优秀博士论文”。 朱相雷（清华），2008年度“全国百篇优秀博士论文”奖 李娜（华中师大），2009 “Gertrude Scharff-Goldhaber Prize” 董忻（中科大-LBNL），2005年度“中国科学院院长奖学金特别奖”；阮丽娟（ustc-BNL),Goldhaber fellow 。。。。。。 作为STAR主要作者已发表的代表性论文

  8. The antihypernucleus observation • The 1st ever-observation of an antihypernucleus: 70 ± 17 ; • The consistent check from hypertriton analysis from the same data set supports the signal: 157 ± 30. J. H. Chen (SINAP), Z.B. Xu (BNL), refer to Z.Xu’s talk, submitted to Science.

  9. 3-D nucleus chart • Extend the 3-D chart of nuclides into the anti-matter sector with strangeness degree of freedom.

  10. y x STAR: preliminary y x x z System size and energy dependence of PID elliptic flow • v2 measurement from Cu + Cu collisions • Glauber eccentricity Similar in the case of CGC eccentricity • NCQ scaling • De-confinement at RHIC • Partonic collectivity • Stronger collective flow in larger system S.S. Shi, IOPP, paper under discussion

  11. Partonic collectivity • At low pT, hydrodynamic mass ordering; • At intermediate pT, B/M grouping behavior; • Hadrons with u-, d-, s-quarks show similar collectivity  Final word on partonic collectivity at RHIC! S.S. Shi, IOPP, paper under discussion； J. H. Chen et al., PRL 99 (2007) 112301

  12. Breaking of NCQ scaling at high pT • NCQ scaling works at (mT-m)/nq < 1.0 GeV/c2: coalescence region; • A divergence at (mT-m)/nq > 1.0 GeV/c2: hard process becomes to dominate? N. Li, IOPP, paper in prepare

  13. Borghini & Ollitrault, PLB 642 227 (2006) Ideal hydro limit ? Ideal hydro: P. Huovinen, private communication Au+Au at 200 GeV Gombeaud & Ollitrault, 0910.0392 • Ideal hydro fails to reproduce the data. • Fluctuation of v2 ,4 plays dominant role! • partial thermalization play a slight role ? • Viscosity ? S.S. Shi and N. Li, IOPP

  14. Hydro limit STAR preliminary Centrality Dependence STAR Au + Au 200 GeV : PRC77, 054901 (2008) STAR: preliminary S. Voloshin, A. Poskanzer, PL B474, 27(00). D. Teaney, et. al., nucl-th/0110037 Au+Au and Cu+Cu at 200 GeV: • NcQ scaling for each centrality bin => partonic collectivity • Collectivity: Driven by number of participants, NOT by eccentricity. • Larger v2/part indicates stronger flow in more central collisions. • Right: The system created in collisions at RHIC is not fully thermalized.

  15. STAR preliminary STAR preliminary Anti-flow/3rd flow component, with QGP  v1 flat at middle rapidity. Brachmann, Soff, Dumitru, et. al. , PRC 61 (2000) 024909. L.P. Csernai, D. Roehrich ,PLB 458, 454 (1999). M.Bleicher and H.Stocker, PLB 526,309(2002). Collapses of proton v1 ? • First measurement of antiproton direct flow; • Collapses of proton v1 • Kaon, less shadowing due to the smaller X-section; Negative v1 slope for Kaon, consistent with the ‘anti-flow’ picture J. Y. Chen, IOPP, paper in preparation; see her talk this afternoon!

  16. The bulk strangeness production & nuclear modification factor in d+Au • K0 agree with charged K at low pT,Λ agrees with proton at intermediate pT (2 – 4GeV/c). • Particle type (baryon/meson) dependence of RdAu for pT from 2 to 4 GeV/c; • The strangeness enhancement from central d+Au lies in a trend with peripheral Cu+Cu and Au+Au X. Zhu, Tsinghua U.

  17. STAR preliminary Extend Kaon measurement up to 15 GeV • Charged and neutral kaons are extended up to 15 GeV/c in p+p collisions • The data can provide constraint for pQCD calculation Y. Xu, USTC, paper under discussion

  18. STAR preliminary pT (GeV/c) Understand energy loss RAA(proton)>RAA(pion) at high pT Which is in contrast to the prediction of color charge dependence of Energy Loss. how the gluon jet/quark jet interact with the medium created in Au+Au collisions. RAA(K) ~ 0.4 at high pT > 5.0 GeV/c consistent with the prediction of jet conversion by interaction with the medium in Au+Au. RAA(p) ~ RAA(r0) at high pT: ; Not a mass effect

  19. Heavy flavor measurement J/Psi • Non-photonic electron spectra from a low material run (ToF run8) • J/Psi measurement in p+p and Cu+Cu collisions F. Jin, SINAP; Z.B. Tang, USTC

  20. Heavy flavor energy loss • No suppression of J/Psi RAA at higher Pt, contrast to open charm measurement. • No significant near sideJ/Psi-hadron azimuthal angle correlation, data show low B contribution: (13  5) % . Z.B. Tang, USTC, Phys. Rev. C 80 (2009) 041902 (R)

  21. The Energy scan program: fluctuation K/p fluctuation Net proton kurtosis analysis • Particle fluctuation is a possible signal for QCD critical point: interesting evolution of K/p fluctuations from lowest SPS energies to RHIC energy; • non-monotonic dependence of K/p fluctuation signal. • No strong non-monotonic dependence with √sNN observed. • The data may provide constraint on the location of QGP phase: μB > 200 MeV • The future RHIC beam energy scan program will provide data of μB 100 - 550 MeV J. Tian, SINAP, paper in preparation X.F. Luo, USTC, paper in preparation

  22. Onset of deconfinement: hypertriton vs.√sNN • Baryon-strangeness correlation via hypernuclei: a viable experimental • signal to search for the onset of deconfinement. S. Zhang, SINAP : arXiv:0908.3357

  23. Longitudinal spin transfer to L • The longitudinal spin transfer is sensitive to the polarized parton distribution and polarized fragmentation functions, has been measured: • The present results don’t provide conclusive evidence for a spin transfer signal due to the limited statistics. Q. H. Xu, Shandong U. arXiv: 0910.1428

  24. Summary Comprehensive data from STAR-China Collaboration, provide direct insight to the QCD matter created at RHIC; STAR-full TOF will extend STAR physics capability More precise data, more new ideals, more knowledge ….

  25. Search for QCD Critical point the run-10 BES plan: 7.0 GeV       -   1 week 11.5             -   2.5 weeks 17.3             -   2.5 27.0             -   3.5 39.0             -   1.5 1st-order Phase Tran. / Critical Point Elliptic & directed flow Fluctuations & correlations - Kurtosis analysis on net protons • Turn-off major sQGP signatures already established at top RHIC energies, see what happens: • NCQ scaling? • Hadron suppression? • Pair correlations in ∆φ&∆η ? • hypertriton vs. √sNN ? STAR Collaboration is planning for initial beam energy scan in Run 10 (fall 2009) Primary tool: search for anomalously large particle identified fluctuations with comprehensive particle identification for charged particles provided by TPC + TOF Fully China’s TOF complete in time for run 10 (fall 2009)‏

  26. R&D for New Projects of MRPC Long strip MRPC A Muon Telescope Detector (MTD) for STAR:

  27. Many thanks for the STAR collaboration, especially for the Chinese teams.

  28. TPC(TPX)- tracking pVPD/upVPD - start time measurement MRPC TOF (TOFr) – stop time measurement ID capability of TOF Detectors Particle momentum; dE/dx ~8% resolution /K separation to ~0.6GeV/c k/p separation to ~1.0GeV/c Aim at 100ps time resolution TOF system /K separation to ~1.6GeV/c & k/p separation to ~3.0GeV/c

More Related