Heavy Flavor Physics in RHIC II

1. Heavy Flavor Physics in RHIC II New Detector Capabilities RHIC II Heavy Flavor Meeting BNL 28/April/2005 Manuel Calderon de la Barca Sanchez Indiana University

2. A Comprehensive New Detector at RHIC II P. Steinberg, T. Ullrich (Brookhaven National Laboratory) M. Calderon (Indiana University) J. Rak (Iowa State University) S. Margetis (Kent State University) M. Lisa, D. Magestro (Ohio State University) R. Lacey (State University of New York, Stony Brook) G. Paic (UNAM Mexico) T. Nayak (VECC Calcutta) R. Bellwied, C. Pruneau, A. Rose, S. Voloshin (Wayne State University) and H. Caines, A. Chikanian, E. Finch, J.W. Harris, M. Lamont, C. Markert, J. Sandweiss, N. Smirnov (Yale University) Expression of Interest Document: nucl-ex/0503002 Manuel Calderón de la Barca Sánchez

3. Outline: Topics for Discussion • Is heavy flavor physics interesting to pursue at RHIC II? • Need to convince outsiders too! • If so, what are the most interesting measurements that can be done at RHIC II? • Quarkonia • Open heavy flavor • What are the requirements for making those measurements. • What are the capabilities of the new detector for a heavy flavor programme? Manuel Calderón de la Barca Sánchez

4. Physics at RHIC II Degrees of Freedom of sQGP (Deconfinement) • Heavy Quark Potentials in Excited Vacuum • Quarkonium production mechanism & polarization Origin of Mass (Hadronization & Chiral Symmetry) Origin of Spin (of Proton) Phase(s) of Matter (CGC  QGP) Manuel Calderón de la Barca Sánchez

5. Heavy Flavor and Deconfinement • Are the following statements still valid? : • Measuring quarkonium states, and oberving a suppression pattern, is our most direct way to establish deconfinement experimentally. • Theory: • Heavy quark potentials in Lattice QCD • Suppression pattern can give information of Temperature of the deconfined phase. Manuel Calderón de la Barca Sánchez

6. J/y Suppression: then and now Lattice QCD: Studies of the dissociation temperature of J/y Lattice Internal Energy as Potential: J/y dissolves at T=1.7 Tc Spectral Functions: J/y dissolves at T~ (1.7-2.5) Tc P. Petrevczky, Hard Probes Manuel Calderón de la Barca Sánchez

7. Deconfinement Temperature The major goal: thermometer for early state: Tdiss(Y’) < Tdiss((3S)) < Tdiss(J/Y)  Tdiss((2S))< Tdiss((1S)) • Need to measure full quarkonium spectroscopy. • Need to do it at least in pp, dA, AA Manuel Calderón de la Barca Sánchez

8. Requirements for 3rd Generation Detector • High Rate • Large acceptance  rate + xF coverage Pythia 6.2 Pythia 6.2 Manuel Calderón de la Barca Sánchez

9. Characteristics of Detector  Allow a Unique RHIC II Physics Program A Comprehensive New Detector at RHIC II (R2D) Central detector (|h| 3.4) HCal and m-detectors Forward tracking: 2-stage Si disks Superconducting coil (B = 1.3T) HCal and m-detectors EM Calorimeter Forward magnet (B = 1.5T) Vertex tracking RICH ToF Tracking: Si, mini-TPC(?), m-pad chambers Forward spectrometer: (h= 3.5 - 4.8) RICH EMCal (CLEO) HCal (HERA) m-absorber Aerogel h= 1.2 – 3.5 PID: RICH ToF Aerogel |h|  1.2 SLD magnet Manuel Calderón de la Barca Sánchez

10. Characteristics of R2D Central detector (|h| 3.4) HCal and m-detectors Superconducting coil (B = 1.3T) HCal & m-dets EM Calorimeter RICH Forward spectrometer: (h= 3.5 - 4.8) magnet tracking RICH EMCal (CLEO) HCal (HERA) m-absorber ToF Aerogel h= 1.2 – 3.5 |h|  1.2 Large magnetic field (B = 1.3T) - 3.4 < |h| < 3.4 inside magnet • Tracking • PID out to 20 – 30 GeV/c • EM/hadronic calorimetry • m chambers • Triggering 4p acceptance 3.5 < h < 4.8 forward spectrometer • External magnet • Tracking • RICH • EM/hadronic calorimetry • Triggering Manuel Calderón de la Barca Sánchez

11. Alternative: R2D based on CDF(CDF and CLEO have same field and magnet radius) Manuel Calderón de la Barca Sánchez

12. Quarkonium Rates at RHIC II • Assume L=30 nb-1 • 14 weeks of running, at 50% duty factor • RHIC II Luminosity = RHIC I x 40 • J/y acceptance (in |h|<3, for p>2) = 28% • Estimated trigger efficiency = 60% •  acceptance (in |h|<3, for p>3) = 60% • Estimated trigger efficiency = 60% • sAuAu = 38 nb x (AA)a x 3.6 = 3.5 mb • J/y measured = sAuAu x (eff acc) L= 17 M •  measured yield = 32 K Manuel Calderón de la Barca Sánchez

13. Quarkonium Rates (SLD geometry) J/Y Eg > 2 GeV Eg > 4 GeV ? ?  Au+Au min bias, 30 nb-1: • plepton > 2 GeV/c for J/Y , 4 GeV/c for  Manuel Calderón de la Barca Sánchez

14. Complete program requirements • For a full understanding of charmonium suppression: • understand nuclear effects • suppression vs. recombination • contribution from feeddown ( states) • understand co-mover absorption • charm production cross section Manuel Calderón de la Barca Sánchez

15. Nuclear Effects E866 J/Y data Quark shadowing and final state absorption + Gluon shadowing + Anti-shadowing + dE/dx • absorption, shadowing • from pA compared to pp • important: xF, x1, x2 dependence Manuel Calderón de la Barca Sánchez

16. Acceptance in xF xF dependence: • E866 was fixed target. • To access large xF at RHIC, large rapidity is a must! • R2D with SLD geometry: 10% acceptance at xF=0.3 • Reach xF=0.6 with coverage |h|<4 Manuel Calderón de la Barca Sánchez

17. Lessons from NA50: systematics • Study pA in detail  absorption in nuclear matter Ebinding(Y’) ~ 50 MeV Ebinding(c) ~ 200 MeV Ebinding(J/Y) ~ 640 MeV Similar study requires good statistics in 6 different beam species! In collider, can’t be done without large acceptance. Manuel Calderón de la Barca Sánchez

18. Excitation function • Recombination vs suppression. • √s dependence • pT, centrality • Large acceptance is desirable to achieve reasonable statistics in short time. Manuel Calderón de la Barca Sánchez

19. cc at Tevatron: Luminosity… Summer 2002 Results Tevatron (s = 1.8 TeV) • D0: • s for |y| < 1.8 ! • J/Y, Y’, c1, c2 • (1S,2S,3S) 4.8 pb-1 of data ~30% systematic uncertainty Luminosity: 114 pb -1 Needs tons of integrated luminosity! Not an easy measurement. Manuel Calderón de la Barca Sánchez

20. cc Feed-down in R2D, g Acceptance To measure cc decay & determine feed-down to J/y cc J/y + g, must have large forward acceptance for g Manuel Calderón de la Barca Sánchez

21. Measuring  : Why and How resolution 8.5 ‰ @ 4.9 GeV CDF  m+ m- Tracking chamber in 1.4 T field PRL 75 (1995) 4358 • All states are interesting for measuring T • In AA: Less affected by co-mover absorption. • Need excellent resolution, e.g. CDF • B=1.4 T • Muon capabilities Manuel Calderón de la Barca Sánchez

22. m+m- in R2D • Measure 1s,2s,3s in AA • 1s is most bound, may not dissolve at RHIC. • Ratio s(3s)/s(1s) very sensitive to deconfinement. • Trigger on is  possible even in Au+Au. • Most luminosity- hungry measurement. • In 30 nb-1, yield in R2D • 1s = 31K • 2s = 5.5 K • 3s = 6 K • Ratio measurement feasible! Manuel Calderón de la Barca Sánchez

23. Charm Production RHIC s = 200 GeV • Drell-Yan dominates only at much larger masses. • Can’t use J/y/DY ratio • Must measure charm s • May be the only reference at RHIC • Production dominated by gluons in both cases. • Open charm reconstruction: • Particle identification • Precision inner tracker. Manuel Calderón de la Barca Sánchez

24. Measurements in pp • Reference for AA of course. • Still unanswered questions on quarkonium production. • Polarization • Acceptance in cos(q*) • pT dependence • J/y polarization in AA? • There’s a huge gap for studies of charmonia in hadronic collisions between fixed target • (38 GeV and 1.8 TeV) RHIC is right in between Manuel Calderón de la Barca Sánchez

25. A complete onium program • In pA nuclear absorption: dependent on xF or x2 ? • In AA: Full spectroscopy , cc: important! Need Luminosity. R2D • In pp: understand charm production (singlet vs octet model) Manuel Calderón de la Barca Sánchez

26. Summary • In terms of quarkonia physics RHIC-II is not too far behind LHC • s(LHC)/s(RHIC) = 9 (GRV-HO) – 25 (MRS-D1) • RHIC-II: 5  higher L • RHIC: > 5 times longer AA running • Measuring “just” J/Y is not enough to extract a physically meaningful result  AA, pp, pA as function of pT, xF, cos*, centrality, reaction plane • Given a 3rd generation detector and RHIC-II luminosity allow a world class measurement of quarkonium in pp, pA, AA at RHIC energies. Manuel Calderón de la Barca Sánchez

27. Addressing additional Physics Unique New Physics Programs at RHIC II: • g - jet/leading particle physics program • flavor dependent modification of fragmentation due to medium • Quarkonium physics program • deconfinement, initial conditions, nuclear effects Unique Physics Contributions to: • Gluon saturation (CGC) • Chiral symmetry restoration • Structure and dynamics of the proton For discussion during the workshop… Manuel Calderón de la Barca Sánchez

28. Preliminary Budget • Central detector (|h| < 3) $ 57 M • Magnet $ 2 M + in kind (SLD) • Coil (replace with superconducting) $10 M • Tracking (Silicon or Gas) $15 M (inc. STAR upgrade) • Vertex (APS) $ 2 M (inc.STAR upgrade) • HCAL (streamer tube exchange) $ 2 M + in kind SLD • Muon chambers in kind SLD • EMCAL • Central $ 1 M + in kind (STAR, D0) • Endcap $ 10 M • PID • RICH (mirrors from SLD) $ 12 M • TOF $ 1 M in kind (STAR) • Aerogel $ 2 M • Forward detector (h = 3-4) $ 11 M • Magnet $ 1 M + in kind D0 • Tracking (Silicon) $ 5 M • HCAL $ 2 M + in kind HERA • PID – RICH $ 2 M • EMCAL $ 1 M + in kind CLEO • Combined DAQ/TRG$ 15 M • Detector TOTAL $ 83 M • Conventional facilities $ 18 M $101 M Manuel Calderón de la Barca Sánchez