1. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 1 Bulk Properties of QCD – matter at Highest Colider Energies Kai Schweda, University of Heidelberg / GSI Darmstadt

2. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 2 QCD Phase Diagram

3. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 3 Outline Identify and study QCD bulk-matter with partonic degrees of freedom: Gobal observable  multiplicity Chemical freeze-out, T ch and  B Partonic collectivity, T fo and  T Heavy – quark collectivity Summary

4. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 4 Mid  rapidity Densities PHOBOS fit HIJING BBar Armesto et al. AMPT Eskola CGC KLN ASW DPMJET-III EHNRR  at LHC, dN/d   1000  3000  estimate energy density Theory points: HI at LHC – last call for predictions, CERN, May 2007.PHOBOS compilation: W. Busza, SQM07.

5. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 5 EoS from Lattice QCD 1) Large increase in  !  Large increase in Ndof: Hadrons vs. partons 2) T C ~ 160 MeV 3) Boxes indicate max. initial temperatures  Longest expansion duration at LHC  Expect large partonic collectivity at LHC Z. Fodor et al, JHEP 0203:014(02) C.R. Allton et al, hep-lat/0204010 F. Karsch, Nucl. Phys. A698, 199c(02). LHC ?RHICSPS

6. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 6 Chemical Freeze - out

7. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda Hadron Yield  Ratios 1) At RHIC: T ch = 160 ± 10 MeV  B = 25 ± 5 MeV 2)  S = 1.  The hadronic system is thermalized at RHIC. 3) Short-lived resonances show deviations.  There is life after chemical freeze-out. RHIC white papers - 2005, Nucl. Phys. A757, STAR: p102; PHENIX: p184; Statistical Model calculations: P. Braun-Munzinger et al. nucl-th/0304013.

8. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 8 Chemical Freeze-Out vs Energy A. Andronic et al., NPA 772 (2006) 167. With increasing energy: T ch increases and saturates at T ch = 160 MeV Coincides with Hagedorn temperature Coincides with early lattice results  limiting temperature for hadrons, T ch  160 MeV !  B decreases,  B = 1MeV at LHC  Nearly net-baryon free !

9. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 9 Baryon Ratios Compilation: N. Xu With increasing energy: Baryon ratios approach unity At LHC, pbar / p  0.95  challenge, need 1% precision to address net-baryon transport !

10. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 10 Partonic Collectivity

11. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 11 Elliptic Flow Theory points: C.M. Ko – last call for predictions, CERN, May 2007. “Elliptic flow is larger for pions but smaller for protons at LHC than at RHIC”.  This is expected from simple, hydro- like blast-wave fits !  larger collective flow: mass ordering more pronounced !

12. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 12 Collectivity  Energy Dependence  Collectivity parameters and increase with energy  Two extreme secenarios: (a) T fo  T ch AND  T  0.8  pure partonic collectivity at LHC! (b) T fo  T ch,  T  0.3  no collectivity, no QGP !

13. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda Quark Masses 1)Higgs mass: electro-weak symmetry breaking. (current quark mass) 2)QCD mass: Chiral symmetry breaking. (constituent quark mass) éStrong interactions do not affect heavy-quark masses. éImportant tool for studying properties of the hot/dense medium at RHIC and LHC. éTest pQCD predictions at RHIC and LHC. Total quark mass (MeV) X. Zhu, M. Bleicher, K.S., H. Stoecker, N. Xu et al., PLB 647 (2007) 366.

14. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 14 Charm Correlations c-cbar are correlated Pair creation: back to back Gluon splitting: forward Flavor excitation: flat Correlations vanish  frequent interactions among partons !  probe light-quark thermalization ! Pythia calcs.: G. Tsiledakis.

15. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 15 Hadronic Re-scattering  Hadronic re-scattering can not completely wash out DD-correlations  Frequent partonic re-scattering needed  light quark thermalization ! X. Zhu, M. Bleicher, K.S., H. Stoecker, N. Xu et al., PLB 647 (2007) 366.

16. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 16 J/  Production  suppression, compared to scaled p+p  regeneration, enhancement Low energy (SPS):few ccbar quarks in the system  suppression of J/  High energy (LHC): many ccbar pairs in the system  enhancement of J/   Signal of de-confinement + thermalization of light quarks ! (SPS) P. Braun-Munzinger and J. Stachel, Nature 448 (2007) 302.

17. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 17 Predictions for LHC  large ccbar production at LHC  corona effects negligible  regeneration of J/  dominates  striking centrality dependence Signature for QGP formation !  Initial conditions at LHC ? A. Andonic et al., nucl-th/0701079.  cc

18. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 18 Pb+Pb  ccc / D : p+p Multiply Heavy-flavored Hadrons F. Becattini, Phys. Rev. Lett. 95, 022301 (2005); P. Braun-Munzinger, K. Redlich, and J. Stachel, nucl-th/0304013.  Statistical hadronization - de-confined heavy-quarks - equilibrated heavy-quarks  Enhancement up to x1000 !  Measure  cc,  cc, B c, (  ccc )  Need total charm yields  Probe deconfinement and thermalization @ LHC  QGP ! Quarks and gluons  hadrons c c c x1000

19. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 19 Heavy  Quark Production 1)Charm x 10 2)Beauty x 100 3) Heavy-quarks abundantly produced at LHC ! STAR data: A. Suaide, P. Djawothoto QM2006; Calcs.: R. Vogt.

20. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 20 ATLASCMS Low – momentum  CMS/ATLAS: Si only tracking  CMS: p T > 0.150 GeV Mid  Rapidity Performance CMS: TDR.v2, CERN-LHCC-2007-009; ATLAS: B. Cole, SQM2007; ALICE: PPR.vol.II, J. Phys. G 32 (2006) 1295.  ALICE: large momentum coverage in full azimuth  address bulk properties !  characterize Quark Gluon Plasma !

21. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 21 J/   e + + e - Reconstruction  J/   e+ + e-  identify electrons through their transition radiation  Precise Measurement of Quarkonia ! J/  : c c  : b b

22. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 22  Measure secondary vertex  Direct reconstruction of D 0  precise measurement of total heavy-quark yield  address heavy – quark collectivity ! D  Meson Performance ALICE: PPR.vol.II, J. Phys. G 32 (2006) 1295.

23. ISMD, Berkeley, Aug 4  9, 2007 Kai Schweda 23 Summary  Bulk properties at LHC: dN / d   1000 – 3000 T ch  160 ± 10 MeV,  B  0 – 5 MeV T fo  T ch  all collectivity from partonic stage = 0.8 ± 0.05 (c),  0.08  Measure spectra, correlations and v 2 of: D 0, D +, D s, J/  b,  to identify and characterize QGP !  ALICE is well suited for these studies