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中国与 RHIC-STAR 的国际合作. 马余刚,陈宏芳,程建平 中国 RHIC-STAR 合作组: 中国科大,清华大学,上海应物所, 华中师大,高能所,近物所 2005/6/28-29. outline. Chinese RHIC-STAR Group TOFr and Physics Results Impact of Chinese RHIC-STAR Group Physics with Full TOF Project Conclusion. Chinese RHIC-STAR Group --
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中国与RHIC-STAR的国际合作 马余刚,陈宏芳,程建平 中国RHIC-STAR合作组: 中国科大,清华大学,上海应物所, 华中师大,高能所,近物所 2005/6/28-29 第59届东方论坛,上海
outline • Chinese RHIC-STAR Group • TOFr and Physics Results • Impact of Chinese RHIC-STAR Group • Physics with Full TOF Project • Conclusion 第59届东方论坛,上海
Chinese RHIC-STAR Group -- History and present organization 第59届东方论坛,上海
US-China Collaboration on STAR/ RHIC • A STAR-China collaboration has been established (Six Institutions from China) • University of Science and Technology of China, Hefei (USTC) • Tsinghua University • Shanghai Institute of Applied Physics (SINAP) • Central China Normal University, Wuhan (CCNU) • Institute of Modern Physics, Lanzhou(IMP) • Institute of High Energy Physics, Beijing (IHEP) • Chinese collaborators are playing a major role in physics analyses involving open charm, Cronin effect, and elliptic flow as part of STAR’s focus on studies of a new state of matter (the quark-gluon plasma) at RHIC • Chinese groups are leading in prototyping and development for a large-area MRPC time-of-flight detector for STAR. • This is the first major US-China collaboration on high energy nuclear physics and we have had a very successful beginning. • The STAR-China Time-of-Flight Construction Project has been covered under the US-PRC HEP Agreement since 2001 to ensure smooth construction of the TOF detector and operation of the STAR-China collaboration. 第59届东方论坛,上海
Major Milestones of STAR-China TOF Project • CCNU and IHEP joined STAR collaboration in 1999 for TOFp; SINAP, USTC, Tsinghua and IMP joined STAR collaboration in Oct. 2001. • USTC team began MRPC R&D in Aug. 2000 with the supports of NSFC, STAR and other Chinese collaboration institutions. • Joined in US/PRC Cooperative Agreement on High Energy Physics since 2001 (22nd Meeting) • Prototype MRPC (multi-gap resistive plate) time-of-flight detectors, produced jointly between USTC and Rice Univ. and operated successfully in STAR (2002-3 and 2003-4 RHIC runs). Physics results on identified particle spectra and on semi-leptonic charm decays have been published. • Approval of "RHIC-STAR Physics and the Construction of Barrel STAR-TOF” by the National Natural Science Foundation of China (Sept 10, 2004, Budget: 1.5M USD) • Approval of the STAR TOF upgrade proposal by BNL Technical Advisory Committee and Submission of the Proposal to DOE (July 2004) • Technical Review of proposal by DOE, planned Aug. 2005 • Suppose DOE approval in Oct. 2005, full construction start October 2005 第59届东方论坛,上海
MRPC TOF Barrel R&D • RUN 2002-3: TOF installed in STAR • 24 MRPC modules produced at University of Science Technology China • 6-channel front-end cards, with amplifiers and discriminators, CAMAC read-out • Run 2003-4: TOF installed in STAR • 5 new modules from USTC and 5 from Tsinghua University, Tsinghua developed automated techniques for manufacturing • 24-channel front-end cards with amplifier and discriminator • RUN 2004-5, TOF installed in STAR, • 16 new modules from Tsinghua • First time use of full on-board read-out electronics: digitization of data on-board • First use of ALICE PCI-PC based DAQ 2002 2004 G. Eppley et al. 第59届东方论坛,上海
The STAR Barrel TOF MRPC Prototype Prototype Tray Construction at Rice University MRPC design developed at CERN, built in USTC/China 28 MRPC Detectors; 24 made at USTC FEE Neighbor CTB Tray EMC Rails 70 ps, 2 meter path Strong team including 6 Chinese Institutions in place Completed Prototype 28 module MRPC TOF Tray installed in STAR Oct. ‘ 02 in place of existing central trigger barrel tray 第59届东方论坛,上海
batch production 40 MRPC production, more than 80% of eligible rate , good performance in on-line testing at RHIC-STAR (Tsinghua) 第59届东方论坛,上海
Chinese Proposal to NSFC Project Leader: Yu-Gang Ma (SINAP) Deputy Leaders: Hongfang Chen (USTC) Jian-Ping Cheng (Tsinghua) Liaison person: Huanzhong Huang (UCLA) • Studies of the strong interaction matter at high temperature/density and searching for QGP (Yu-Gang Ma, SINAP) (SINAP, CCNU, USTC, Tsinghua etc.) focus on the collective dynamics of rare particles, heavy quark production, hadronic evolution dynamics and search for multi-quark state particles • Design and Mass production of MRPC modules for STAR-TOF (Jian-Ping Cheng, Tsinghua) (Tsinghua, USTC) 3840 MRPC for 120 tray, additional 6 tray (70% Tsinghua/30% USTC) • Quality control and calibration for STAR-TOF (Xiao-Lian Wang, USTC) (USTC, Tsinghua) 第59届东方论坛,上海
The Proposal of RHIC-STAR Full TOF Construction Proposed major construction responsibilities: • Chinese STAR Groups: MRPC Production and Quality Assurance – NSFC/CAS/MoST (Approved in Sept, 2004) (Special thanks for Huanzhong, Nu, Zhangbu, Xinnian et al. for many important suggestions and helps) • US STAR Groups: Electronics and Integration etc – DOE Project Manager: G. Eppley (with DOE) • Monetary Contributions: China ~ US$2.5 M (US$ 1.5M from NSFC/CAS/MoST) US- DOE ~ US$4.5 M 第59届东方论坛,上海
STAR TOFr and Physics Results TOF prototype: 1/120 coverage of Barrel STAR 第59届东方论坛,上海
PID TPC alone TOF “alone” p k TOF=110ps TPC alone PID range: pi/k ~0.6 GeV/c, (pi,k)/p ~1.5GeV/c; TOF “alone” PID range: pi/k ~1.6GeV/c, (pi,k)/p ~ 3.0GeV/c m2 m2 第59届东方论坛,上海
Preliminary pion spectra till high pT TPC+TOF: • TPC+TOF: • Pion: 0.-~10 GeV/c • Kaon: 0.2-~3GeV/c • Proton: 0.2-~5 GeV/c • TPC: • Pion: 0-~0.6GeV/c • Kaon: 0.2-~0.6GeV/c • Proton: 0.2-~1 GeV/c • TOF: • Pion: 0.2-~1.6GeV/c • Kaon: 0.2-~1.6GeV/c • Proton: 0.2-~3 GeV/c 第59届东方论坛,上海
Lepton decay from heavy quark Electron identification Electorns mixed with pions if only dE/dx of TPC is used to identify particles Combined with TOF,electrons can be separated from pions cleanly X. Dong, Z.B. Xu, LJ Ruan, J Wu et al 第59届东方论坛,上海
RAuAu and RdAu of f ______________ STAR Preliminary • RdAu of is closer to that of p and k than that of p • Particle production at intermediate pT region is sorted by the particle’s type, not the mass 第59届东方论坛,上海
Preliminary results v2 1.the elliptic flow of Φ-meson gives similar behavior of Ks but distinguish from Λ 2. a NCQ-scaling has been observed in Φ-meson 3. error bars in higt pt range (2.5GeV,5.0GeV) are still large 0-80% STAR Preliminary data AMPT calc. 第59届东方论坛,上海
Impact of Chinese RHIC-STAR Collaboration 第59届东方论坛,上海
Organizing International workshop Host: • Aug 2002: 1st International CCAST Summer School and Workshop on “QCD and RHIC Physics” in CCAST-WL, Beijing. Organized by Profs. X.L. Wang and P. F. Zhuang. There were ~15 foreign speakers invited, ~100 participants • Oct 2003, 1st STAR Regional Collaboration Meeting, USTC; ~10 STAR speakers invited • Aug 2004: 2nd International CCAST Summer School and Workshop on “QCD and RHIC Physics” in CCAST-WL, Beijing. Organized by Profs. Y.G. Ma, E.K. Wang and J.H. Fu. There were 19 foreign speakers and 22 domestic speakers, ~140 participants. • Oct 2004: International Workshop on “Collective Dynamics inRelativistic Heavy Ion Collisions” @ USTC, Organized by X.L. Wang and Nu Xu • 19-24 June 2005: 3rd International Workshop on “QCD and RICH Physics” was organized by CCNU and CCAST et al.,, Wuhan; 20 foreign speakers, ~140 participants 第59届东方论坛,上海
Talk @ Int. Conference QM2006 in Shanghai: • The proposal to host “Quark Matter 2006” in Shanghai was accepted during QM2004 in Oakland. Shanghai Institute of Applied Physics and Central China Normal University will co-organize the QM2006 in Shanghai, preliminary date Nov 16-22, 2006 Co-chairs: Zhiyuan Zhu (SINAP) & Xu Cai (CCNU) Honor Chair: T. D. Lee Taks in some international conferences: Conference Talks: QM2004: one oral presentation (Ruan) SQM2004: three oral presentations (Cai, Ruan, Ma) ICEHP2004: one oral presentation (Wu) QM2005: one Plenary Talk (Dong, from TOF phys results) one parallel talk (Cai) …… 第59届东方论坛,上海
Our excellent students PhD Dissertations (incomplete statistics) : Jinghua FU (CCNU): 获二○○五年全国优秀博士学位论文 Shengli HHUANG (USTC), Lijuan RUAN (USTC),Zhixi LIU (CCNU) Xing DONG (USTC):获二○○四年中国科学院院长奖学金特别奖 More PhD Students are involved in RHIC-STAR physics Chinese Principal authors of STAR Publications or works: Jinghua Fu et al.: Flow of Ks and for 130GeV/c Au+Au (Phys. Rev. Lett. 89, 132301 (2002).) Xin Dong et al. : electron spectra fro open Charm (nucl-ex/0407006), PRL94, 062301 (2005) Lijuan Run et al.: Cronin Effect (nucl-ex /0309012 ), Phys Lett B 616, 8 (2005) Lijuan Ruan (for the STAR Collaboration), π, K, p and production from Au+Au collisions at 62.4 GeV, J. Phys. G: Nucl. Part. Phys. 31 S1029-S1033 (2005) Xiangzhou Cai (for the STAR Collaboration) Production of K0s, Λ and Ξ from 200 GeV d+Au collisions at RHIC, J . Phys. G: Nucl. Part. Phys. 31 S1015-S1018 (2005) Ming Shao, Pion, Kaon, and (Anti-) Proton Production in Au+Au Collisions at \srt = 62.4 GeV, J.Phys. G31 (2005) S85-S92 Shengli Huang et al.: azimuthal dependent fluctuation Zhixu Liu et al.: flow of Ks and for 63 GeV/c Au+Au Guoliang Ma et al. : flow and spectra of for 63 63 GeV/c Au+Au Jinhui Chen et al., phi flow Jiaxu Zuo et al., multi-strange partcile spactra, ……………. 第59届东方论坛,上海
Physics with the full coverage of TOF 第59届东方论坛,上海
STAR TPC + TOF (MC) • Central (top 10%) collisions • acceptance with TPC: • p: ~ 60% • K: ~ 60% • p: ~ 50% • acceptance with TPC+TOF: • > 95% for all particles • S/N for freconstruction will • increase by a factor of 5-10 • v2 measurement possible Z. Liu, F. Liu, et al. 第59届东方论坛,上海
STAR TPC + TOF • TOF will increase V0 reconstruction efficiency. In the case of W, a factor of 5 – 10 increase expected in the region pT ~ 3-5 GeV/c! • TOF will also help future D meson reconstruction – increasing S/N ratios, same way for other resonances. • (D0 → K−+) • (D0-bar → K+−) • 3) In the case for f, a factor of 5-10 increase in S/N ratio is expected. • =>K + + K - (49.1%) H. Long et al. 第59届东方论坛,上海
STAR TPC + TOF W v2 measurements For integrated W v2 : needs ~ few 106 MiniBias events. More events without TOF Multi-years running. pT dependence W v2: for <20% around pT ~ 5 GeV/c, needs ~ few 10th 106 MiniBias events with TOF almost impossible without TOF in middle Pt STAR 200 GeV results: T = 0.45 GeV dN/dy = 0.64, sum of W- and W+ < v2 > ~ 8% all are usable events (1.5 -3 factor) ideal With TOF w/o TOF 第59届东方论坛,上海
TOF and Hyperon Embedded Data: L reconstruction with and without PID information! A Factor of 3 !! Input spectrum: T = 350 MeV 第59届东方论坛,上海
Chinese interests • Collective dynamics for rare particles • Heavy flavor quarks • Search for multi-quark state particles • Fluctuations • Correlation of rare particles • Hadronic evolution dynamics: resonance • ……. 第59届东方论坛,上海
Collective flow in partonic level:Does the Recombination model work for heavy particles or strange quark? how about flow of electron, , , D, J/ v2(p) ? Need Full TOF for good efficiency and statistics 第59届东方论坛,上海
Heavy flavor quark • Initial condition • J/ suppression • Heavy quark energy loss D0 Sensitivity in pT Charm quark mostly produced from the initial fusion of partons (mostly gluons) • Important Measurement: Open Charm • TOF helps by a factor of ~5 (all PT) • TOF + Active Pixel Sensitive: x8 • Other Open Charm States Possible only with TOF • Full Coverage needed 第59届东方论坛,上海
Hadron evolution dynamics:resonance Time scale of resonance state Resonance K*(892) (770) f0(980) (1020) (1232) (1520) (1385) Decay channel K K K ee p pK Branching Ratio % ~100 ~100 dominant 49.2 0.3 >99 22.5 88.2 Width [MeV] 50.7 150 40 to 100 4.46 ~120 15.6 35.8 Life time [fm/c] 4 1.3 40 ~1.6 13 5.6 Increasing factor for statistical significance of the signal • Resonance Parent PT(GeV/c) TPC+TOF • K*0 0-1 2.0 • K*0 1-2 1.85 • K*0 2-3 1.74 • K*0 3-5 1.39 • ______________________ • (1020) 0-2 5.0 • (1020) 2-5 3.42 • ___________________________ • (1520) 0-1.6 11.4 Kinetic Freeze-out --- Interaction ceases Chemical Freeze-out --- formation of hadrons 第59届东方论坛,上海
Potential exotic particles/phenomena: penta-quark states (uudds, uudds!) di-baryons H – (L-L, uuddss) [W-W] (ssssss) strange quark matter……. Discoveries from Unexpected Areas?! RHIC -- Frontier for bulk partonic matter formation (quark clustering and rapid hadronization) -- Factory for exotic particles/phenomena penta-quark states? 第59届东方论坛,上海
Search for multi-quark state particles • Z.Y. Zhang et al., Phys. Rev. C 61, 065204 (2000); Phys. Rev. C66, 015205 (2002) • 3 body decay: 2 body decay: A chrial SU(3) model and analyses of the symmetry properties of two-baryon systems, some features: A deeply bound, Eb ~ 100MeV; A compact object, Rrms~0.63fm, <<Rd may be six strange quark state rather than a di-baryon configuration Phenomenological estimation (coalescence/statistical): yield 10-4_10-7/central Au-Au; Full barrel TOF ~ 100M central AuAu events needed. It is impossible to search di-omega in RHIC without STAR-TOF 第59届东方论坛,上海
Conclusion • We have strong team to collaborate with RHIC-STAR, especially we have excellent young students and excellent overseas Chinese Americans • Chinese Proposal to make B35arrel TOF has been approved by NSFC, we are playing leading role in STAR TOF upgrade • We have great opportunity to do some new and important physics with full TOF 第59届东方论坛,上海
Recall Shanghai TOF meeting for Discussion of NSFC proposal draft, Jan 2003 第59届东方论坛,上海
别有洞天 We have a new scenery ! 第59届东方论坛,上海
Hadron spectra and Cronin effect Traditional Cronin Effect is not the whole story at RHIC TPC With TOFr STAR d+Au from TOFr analysis (USTC+BNL+RICE) Results on KS, L and f will reach higher pT (SINAP+UCLA) 第59届东方论坛,上海
PID dependent Cronineffect PID Cronin Effectnucl-ex /0309012 ) With TOFr 第59届东方论坛,上海
recentlyIn order to know about the elliptic flow of ,, D, J/, Full TOF is necessary for good efficiency and statistics. • In order to improve the measurements of Open Charm, TOF helps by a factor of ~5 (all PT) and Full Coverage needed • In order to investigate the hadronic evolution dynamics, TOF increases important factor for statistical significance of the resonance production. • TOF will significantly enhance the hyperon detection efficiency. RHIC provides a unique environment for possible production of multiply strange di-baryons. 第59届东方论坛,上海
Heavy flavor (D-->e+X) D meson and electron spectra :Dong, ZB, Ruan et al The total photonic backgrounds are shown as solid lines. Dashed lines depict the various contributing sources. The fractions were derived from simulations. Bottom: Ratios of the inclusive electrons over the total back-grounds. signal excesses are visible with pT > 1 GeV/c. With TOF tray 第59届东方论坛,上海
Rcp of f for different collision system STAR Preliminary • yield suppression at intermediate PT in central Au+Au collisions • no clear suppression is showed in the 62.4 GeV Au+Au collision. It become flat at PT>1GeV/c2 • RCP in d+Au collision is enhanced • It is difficult to draw some definite conclusion due to the large error bar Low pT, RCP <1 High pT, RCP >1 第59届东方论坛,上海