1. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC1 Hideto En’yo RIKEN / RIKEN-BNL Research Center Physics with RHIC Spin Collider ---- just taking off ----- Hideto En’yo RIKEN / RIKEN-BNL Research Center Contents Contents  Status of Spin Collider  Physics of Spin Collider  First Results, Highlights  Summery & Outlook

2. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC2 Polarized Proton Acceleration KEK OPPPS, Tuned for RHIC at TRIUMPH 500  A, 300  s Booster: No Spin Resonance Two Rings in the Tunnel AGS: Partial Siberian Snake Transfer Lines to RHIC, Spin transparent

3. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC3 Snake Magnet STAR PHENIX AGS LINAC RHIC Proton and its spin motion in Snake 4 Helical Dipoles – one Snake essential invention for RHIC spin 2 Snakes in each ring Snake axis orthogonal each other Spin is preserved up to 250GeV RIKEN fund

4. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC4 Beam ’ s View Si #1 Si #2 Si #4 Si #3 leftright down up Si #5 Si #6 Carbon filament target (5 m g/cm 2 ) in the RHIC beam Measure recoil carbon ions at  90 º 100 keV < E carbon < 1 MeV Wave-Form Digitizer +FPGA high counting rates (~0.5 MHz) scaler measurement  ~ 3  10 -4 in ~1 minute. Carbon ADC values Arrival time (ns) Coulomb Nuclear Interference Polarimeter STAR PHENIX AGS LINAC RHIC PaNic02 K.Kurita

5. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC5 Luminosity in Year 1 0 50 100 150 200 250 300 350 13579111315171921232527293133 Days into run (from 12/20/01) STAR 300 nb -1 PHENIX 150 nb -1 Machine Luminosity 300 nb -1 /week Peak 1.8x10 30 cm -2 s -1

6. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC6 Polarization in Year 1 Yellow RingBlue Ring

7. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC7 Why polarization was low ? 10% 20% 30% P AGS P RHIC Injection 1 st Year Ramp up Spead Source Improvement New AGS SNAKE 2004-5 AGS motor generator failure ½ ramp up speed 2x resonance effect

8. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC8 Prospect of Machine performance RUN#proton/ bunch [x10 9 ] #bunchBeta* (m) Emittance (  m) L uminosity 10 30 cm -2 s -1 Pol. (%) 2001- 2002 70553251.815-25 2002- 2003 1001121251645-55 2005-?1121??70-80 Design2001121208070

9. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC9 The Spin Experiments STAR PHENIX AGS LINAC RHIC pp2pp Spin Rotators pp elastic Silicons in Roman pot -t down (0.004 GeV/c) 2 b*=10m (special tune)

10. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC10 Spin Physics at RHIC Spin Structure of Nucleon –1/2=(1/2)  +  G+L q +L g  G: gluon polarization  q: Anti-quark polarization –New Structures h 1 : transversity RHIC = polarized parton collider NEW TOOL to study hadronic processes W,Z @500GeV flavor sensitive studies on the structure functions cc/bb Production mechanism Spin in the fragmentation Parity,CP violating interaction? Test of pQCD Use asymmetries sensitive ONLY to the higher orders (A N at high P T etc.) ?QCD triumph? or ?beyond ?

11. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC11 A LL : Double Longitudinal Spin Asymmetry –Useful in extracting quark/gluon helicity distributions A TT : Transversity A N : Twist-3 or T A L : Parity Violation Asymmetries Measurements

12. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC12 Global QCD Analysis AAC Preliminary M. Hirai, H.Kobayashi, M. Miyama et al. Impact of RHIC Spin on  g With RHIC DATA (1year)

13. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC13 Measurements of  q,  q at PHENIX –d small at high x  u/u (  d/d for W  ) flavor selected valence quark polarization  d/d (  u/u for W  ) determination Major background is Z decay (20%) systematic error will be minimized (~1%) with A L Z (~20%)and  (Z) measurements N.Saito Parity violating single Asymmetry unpolarized distribution  polarized distribution

14. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC14 Data from the 1 st polarized pp runs  Run all the time with vertical polarization polarization is too low to perform double spin No gluon information  Commission the detectors for polarized pp  Cross section reference for pp and AA  First measurements of L-R asymmetry at root s = 200GeV

15. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC15 PHENEIX  0 cross section Pt Spectrum over 10 8 magnitude NLO pQCD calculation –CTEQ5M pdf –Potter-Kniehl-Kramer(PKK) – fragmentation function –  = p T /2, p T, 2p T Consistent with data within the scale dependence. PHENIX Preliminary Normalization error of 30% not shown. MB trigger2x2 trigger p T dependent systematic error Spin02 B.Fox (RBRC) QM02 H,Torii(Kyoto) PaNic02 Y. Goto(RIKEN)

16. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC16 PHENIX J/  µ+µ-µ+µ- e+e-e+e- Br(J/  l + l - )  (total) = 226  36 (stat.)  79 (syst.) nb  ( p+p  J/  X ) = 3.8  0.6 (stat.)  1.3 (syst.) µb PHENIX Preliminary Total Cross section vs. the Color-Evaporation Model prediction CEM Parameters are fixed by fitting low energy data The result agrees with the CEM prediction at  s=200GeV Spin02 H. Sato( Kyoto) Panic02 K.Ozawa(CNS) Rapidity distribution compared with PHITHIA simulation

17. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC17 Physics in A N (L-R Asymmetry) useful for local polarimeter for collision point 0 1 2 3 4 5 Rapidity STAR FPD 0 o CAL BBC PHENIX MUON PHENIX CENTRAL STAR TPC pp2pp E704 at Fermilab at  s=20 GeV, p T =0.5-2.0 GeV/c: X F 0.2 0.4 0.6 0.8 PTPT Models:: Transversity, Higher Twist, Fragmentation, kT, Orbital. Etc.

18. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC18 STAR Forward rapidity high x F  0 A N x F ~ E / 100 GeV STAR FPD Preliminary Data Assuming A N (CNI)= 0.013 p T =1.1 - 2.5 GeV/c 0.0 0.2 0.4 -0.2 00.20.40.60.81.0 A N    Systematic uncertainty + － 0.05 Theory predictions at p T = 1.5 GeV/c Collins effect Anselmino, et al. PRD 60 (1999) 054027. Sivers effect Anselmino, et al. Phys. Lett. B442 (1998) 470. Twist 3 effect Qiu and Sterman, Phys. Rev. D59 (1998) 014004. Y.Koike PaNic02 Spin02 G.Rakness(IUCF)

19. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC19 Beam-Beam Counter (BBC) Luminosity Monitor of STAR Scintillator annulus installed around the beam pipe, on the east and west poletips of STAR magnet at ±3.5m from IR ( 2 < |  | < 5) ~7m FPD BBC (West) STAR Magnet + TPC BBC (East) beam pipe Schematic side view of STAR

20. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC20 STAR BBC Asymmetry Measured by RHIC polarimeter BBC Asymmetry Demonstrate that asymmetry sensitivity better than 1/1000 Small since  +  － cancellation ? Spin02 J.Kiryluk(UCLA)

21. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC21 12 O‘clock （ local polarimeter for PHENIX) EM Cal Base PbWO 4 Charge Veto Neutron VetoHadron Cal Base Pb Scintillator W+Fiber Cal Post-shower Spin02 Y.Fukao(Kyoto) Panic02 M.Togawa(Kyoto) 00

22. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC22 12 O’clock

23. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC23 Asymmetries (A N ) seen 0 1 2 3 4 5 Rapidity STAR FPD 0 o CAL BBC PHENIX MUON PHENIX CENTRAL STAR TPC pp2pp X F 0.2 0.4 0.6 0.8 PTPT  0 +10 ~ +20% Charged +1% Neutron - 10%  -3%  0 <3%

24. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC24 Coming Run with longitudinal polarization 3pb -1,P=50% W. Vogelsang STAR JET PHENIX Charged  G will be directly probed expectations

25. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC25 Summary and Outlook RHIC spin program has begun. We have a series of program over 5 years to go. Y2001-2, The first polarized proton collision was successfully done with transversely polarized beam, produced unexpected spin phenomena which may relate to unknown behavior of QCD (transversity etc) Y2002-3, The first measurements of helicity asymmetry will SOON be performed @200GeV. Sizable  G generates surprises in the data. Y2003+, Statistics will be much improved @200GeV, ensuring the determination of  G. “Spin Crisis” will hopefully be solved by then. Y2005+, Weak Bosons will be produced at RHIC, the NEW “flavor sensitive” tool for the anti-quark/quark polarization and unpolarized structure function of anti-quark measurements. beyondAnd beyond…

26. PaNic02 03/10/02 Hideto En'yo RIKEN/RBRC26 Many Thanks To RHIC Spin Collaboration (Spokesman: G. Bunce) Spin physics is an integral part of the goals of the STAR, PHENIX and pp2pp experiments. RHIC Accelerator Spin Group (Spokesman: T.Roser, Project Manager: W.Mackay) RIKEN and RIKEN/BNL Research Center (Group Leaders: H. En’yo, G.Bunce, N. Saito), Theory Group （ W.Forgelsang et.al.) STAR Spin Physics Working Group (Conveners: L. Bland, G. Eppley) PHENIX Spin Physics Working Group (Conveners: Y. Goto, M. Perdekamp) pp2pp Experiment (Spokesman: W. Guryn) BNL Groups: RHIC Spin Group (Group Leader: G. Bunce); KEK Accelerator Group (Y. Mori et al.); Laboratory / University participation Kyoto-U, TITech, ANL, IUCF, KEK and many others.