1. Naohito Saito RIKEN-RBRC Physics at RHIC -Status of the heavy ion collider- Physics at RHIC -Status of the heavy ion collider- Hadron XIII, TIFR, India, 14-20, January, 1999 Naohito Saito RIKEN / RIKEN BNL Research Center Contents 1. Physics at RHIC 2. Status of RHIC 3. Status of Detectors at RHIC 4. Status of PHENIX 5. Physics with PHENIX

2. Naohito Saito RIKEN-RBRC Physics at RHIC Study of QCD in extreme conditions –heavy ion physics - hot and dense limit –spin physics - high Q 2 with spin d.o.f. Heavy Ion Physics –search for a new state of matter - Quark Gluon Plasma –characterize its physical properties Spin Physics –elucidate the spin structure of the nucleon –search for a physics beyond standard model

3. Naohito Saito RIKEN-RBRC Confinement and QGP Quarks are confined in a hadron –No free quark has been observed They can be free at; –high energy asymptotic freedom –high temperature –high density High temperature –a few  sec after big-bang –in relativistic heavy ion collision

4. Naohito Saito RIKEN-RBRC (Partial) List of QGP Signals Debye Screening –Suppression of quarkonium production Chiral Symmetry Restoration –Shift in mass, width of  –Disoriented Chiral Condensation Thermal Radiation of Hot Gas Strangeness and Charm Production Jet Quenching …

5. Naohito Saito RIKEN-RBRC Debye Screening suppression of quarkonium production CERN NA50 claims anomalous suppression of J/  in Pb+Pb collisions at 158A GeV NP A638 (1998) 261c

6. Naohito Saito RIKEN-RBRC Phase Diagram of Hadronic Matter from hadro-chemical analysis At SPS and AGS, the freeze-out points approach the “boundary”. RHIC and LHC should show clearer signal of phase transition Scale uncertainty

7. Naohito Saito RIKEN-RBRC Spin Sum Rule for the Proton Proton spin=1/2  Quark Spin:  valence quark:  u v,  d v sea quark: Quark Orbital Motion:L q Gluon Spin:  G Gluon Orbital Motion:L g Spin Sum Rule

8. Naohito Saito RIKEN-RBRC “Proton Spin Crisis” Successful Description of Baryon  M by Q uark M odel ”quark carries all proton spin” Puzzling Data from polarized lepton-Nucleon scattering  : total quark spin contribution to the proton spin  s: strange quark contribution to the proton spin Fixes for ”Spin Crisis” –Gluon is polarized :  G > 0 –Anti-quark is polarized: indirect decomposition suggests  s<0 –Steeper small-x

9. Naohito Saito RIKEN-RBRC R elativistic H eavy I on C ollider (RHIC) The first collider for –Heavy Ions: e.g. Au+Au at 200A GeV current max: 18A GeV (CERN SPS) –Polarized Protons at 500 GeV current max: 20 GeV (FNAL) RIKEN BNL Collaboration pp luminosity is for enhanced mode. RHIC Accelerator Specification

10. Naohito Saito RIKEN-RBRC RHIC Spin Project RHIC Spin Project RIKEN-BNL Collaboration acceleration and PHENIX Muon Arm for Spin RIKEN BNL Research Center PHENIX-Computing Center in Japan Siberian snake to maintain polarization Spin Rotators to obtain given polarization

11. Naohito Saito RIKEN-RBRC RHIC as a Polarized Collider AGS Polarization

12. Naohito Saito RIKEN-RBRC The End Game Plan

13. Naohito Saito RIKEN-RBRC RHIC Experiments 2 Large Experiments –PHENIX@8 o’clock ~450 from 41 inst –STAR@6 o’clock ~370 from 37 inst 2 Small Experiments –Phobos@10 o’clock 9 institutions –Brahms@2 o’clock ~50 from 6 countries

14. Naohito Saito RIKEN-RBRC STAR Detector STAR Detector S olenoidal T racker A t R HIC A Large TPC-based Detector System

15. Naohito Saito RIKEN-RBRC STAR Detector in Assembly Hall

16. Naohito Saito RIKEN-RBRC BRAHMS Experiment Charged Hadrons over a wide range of p T and y to study production mechanisms

17. Naohito Saito RIKEN-RBRC PHOBOS Experiment Two-arm magnetic spectrometer of “table-top” size Exclusive use of micro- strip silicon detectors Charged hadrons and leptons at selected solid angles

18. Naohito Saito RIKEN-RBRC PHENIX Detector System 2 Muon Arms –3 stations of tracking chambers –5 layers of  - identifier Central Arm –EMcal –Tracking –RICH, TOF –MVD –BB

19. Naohito Saito RIKEN-RBRC PHENIX Muon Arms Magnet+C athode S trip C hamber +MuID Magnet CSC -100  m 3stations 3 gaps 3 planes MuID 5 layers absorber: North:30+10+10+20+20 cm South:20+10+10+20+20 cm

20. Naohito Saito RIKEN-RBRC PHENIX at Experimental Hall

21. Naohito Saito RIKEN-RBRC PHENIX Priorities in Year-1 1. Sufficient Au+Au running to –Turn-on, calibrate, commission all installed detectors –Reach 20  b -1 integrated L (to tape) 2. Polarized proton commissioning in one ring 3. Anything else (e.g. p+A, lower E, lighter A) Coherent request with STAR RHIC Spin Collaboration ( spokesman: G. Bunce ) proposal –4 weeks of commissioning in the first year

22. Naohito Saito RIKEN-RBRC Example of Year-1 Physics Measurement of hard processes: –General: an auto-generated plasma diagnostics –Specific: dE/dx in deconfined phase ~10x larger than normal nuclear matter NP B483 (1997) 265, NP B484 (1997) 291 Will measure –with an open trigger –study as a function of centrality

23. Naohito Saito RIKEN-RBRC Spin Physics at RHIC Spin Structure of the Nucleon – : Gluon polarization via ,  0,heavy quark productions –  : Anti-quark polarization via Drell-Yan (W,Z,  *) – : Quark transversity Symmetry Tests –parity violating effects, e.g. compositeness QCD Selection Rule –switch off gluon; a TT /a LL <<1 Single Transverse Spin Asymmetry A N –large at low Energy; higher-twist? ; k T asymmetry?

24. Naohito Saito RIKEN-RBRC Prompt Photon Production Gluon Compton Dominates  gluon Comptonannihilation Theoretically clean Experimentally Hard Object Fine granuality of PHENIX EMcal helps

25. Naohito Saito RIKEN-RBRC Prompt Photon A LL and  G Model Calculation with P YTHIA and BS/GS95 @200 GeV BS  G>2 GSA  G =1.71 GSB  G =1.63 GSC  G =1.02

26. Naohito Saito RIKEN-RBRC Anti-quark Helicity Distribution W production –helicity of quarks definitely defined via V-A nature –flavor almost fixed: flavor analysis possible –PHENIX-Muon Arms, EMcal important W yield with 800 pb -1 PYTHIA w/ GRV94LO checked against CDF data

27. Naohito Saito RIKEN-RBRC Prediction and Projected Error Ldt=800 pb -1

28. Naohito Saito RIKEN-RBRC Charmonium Production Asymmetry Prediction with Color Octet Model Yield Estimation with Color Octet Model by Naoki using COM in PYTHIA (hep-ph/9706270) See D. Kharzeev’s transparencies at Spin Discussion at http://rikweb.rhic.bnl.gov/rsc/write-up/Kharzeev/kharzeev1.html

29. Naohito Saito RIKEN-RBRC HI Collision in STAR Detector Ultra High Particle Density

30. Naohito Saito RIKEN-RBRC Summary RHIC is a unique facility to study QCD in extreme conditions: –heavy ion physics –spin physics RHIC is preparing for the transition from Construction phase to Operation phase. NovemberFirst Physics Run will start in November this year!