1. Ágnes MócsyQWG Meeting BNL June 27-30 06 1 Quarkonia above Deconfinement and Potential Models Quarkonia above Deconfinement and Potential Models Ágnes Mócsy

2. QWG Meeting BNL June 27-30 06 2 summarysummary potential models vs lattice QCD  some features of quarkonia spectral functions agree BUT there are unreconciled inconsistencies  1st analysis of correlators from potential models  our attempts to understand the discrepancies

3. Ágnes MócsyQWG Meeting BNL June 27-30 06 3 J/  suppression “unambiguous” signal of deconfinement T. Matsui, H. Satz 1986  in quark-gluon plasma the color Coulomb-force between heavy Q and  Q gets Debye-screened R screening < R Q  Q quarkonium dissociates R screening < R Q  Q quarkonium dissociates  sequential suppression F. Karsch, M. Mehr, H. Satz 1988 F. Karsch, M. Mehr, H. Satz 1988  modification of quarkonia properties with temperature could tell about deconfinement it all started in 1986 T  ’(2S)  c (1P) J/  (1S ) 0.9fm0.7fm0.4fm

4. Ágnes MócsyQWG Meeting BNL June 27-30 06 4 since 2004 from QCD correlation functions of hadronic currents reliably calculated spectral function  ( ,T) spectral function  ( ,T) also: T. Umeda T. Hatsuda, M. Asakawa S. Datta et al 2004 1P charmonium is gone at 1.16T c P. Petreczky et al 2006 M E M  c0

5. Ágnes MócsyQWG Meeting BNL June 27-30 06 5 fromfrom 1S charmonium survives up to 1.5T c correlator  spectral function does not change correlator  spectral function does not change spectral function  properties do not change spectral function  properties do not change contradiction with early potential model predictions S. Datta et al 2004 cccc

6. Ágnes MócsyQWG Meeting BNL June 27-30 06 6  At what temperature do heavy quark bound states disappear?  Can modification of quarkonia properties be understood via a temperature-dependent screened potential?  If yes, what is the potential?  If not, how can we explain quarkonium dissociation? What is the mechanism behind quarkonia melting?

7. Ágnes MócsyQWG Meeting BNL June 27-30 06 7 potential MODEL heavy Q-  Q interactions are mediated by a potential heavy Q-  Q interactions are mediated by a potential confined deconfined J/  r V(r) T = 0 T > T c success for spectroscopy lattice confirmed obtainable from QCD we don’t know assume a temperature-dependent potential V(r,T) assume a temperature-dependent potential V(r,T) & solve Schrödinger’s equation to obtain properties of Q  Q

8. Ágnes MócsyQWG Meeting BNL June 27-30 06 8 screened potentials  screened Cornell potential:  fitted lattice internal energy:  Wong potential: mixture of lattice internal & free energy mixture of lattice internal & free energyCommon: all could keep the J/  up to 1.5 T c all could keep the J/  up to 1.5 T c Is this enough to be consistent with lattice? E. Shuryak, I. Zahed, 2004 W. Alberico et al 2005 C. Y. Wong 2005 F. Karsch, M. Mehr, H. Satz, 1988 O. Kaczmarek et al 2004

9. Ágnes MócsyQWG Meeting BNL June 27-30 06 9 bound states/resonances + continuum bound states/resonances + continuum I. model spectral function  += ÁM, P. Petreczky, hep-ph/0411262 hep-ph/0512156 hep-ph/0512156 hep-ph/0606053 hep-ph/0606053 Schrödinger eq with V(r,T) M i (T) bound state mass F i (T) amplitude asymptotic value of V(r,T) s 0 (T) threshold

10. Ágnes MócsyQWG Meeting BNL June 27-30 06 10  c0 correlator the  c0 is gone just above T c increase in correlator due to continuum qualitative agreement with lattice ÁM, P. Petreczky 2005 S. Datta et al 2004

11. Ágnes MócsyQWG Meeting BNL June 27-30 06 11  c correlator   c correlator does not agree with lattice increase due to continuum, decrease due to amplitude reduction  correlator implies change in spectral function  disagrees with lattice feature for all screened potentials ÁM, P. Petreczky 2005 S. Datta et al 2004

12. Ágnes MócsyQWG Meeting BNL June 27-30 06 12  no assumption for spectral function needed  drastic change in 1S mass & amplitude  inconsistent with lattice  even though 1S survives the spectral function is strongly modified II. nonrelativistic Green’s function lattice internal energy S-wave A. Jakovác et al 2006 ÁM, P. Petreczky, J. Casalderrey-Solana, in prep.

13. Ágnes MócsyQWG Meeting BNL June 27-30 06 13 Green’s fct. cont.  inconsistency with lattice data is even worse how could we - can we - produce agreement with lattice? Wong potential ÁM, P. Petreczky hep-ph/0606053 A. Jakovác et al 2006

14. Ágnes MócsyQWG Meeting BNL June 27-30 06 14 instead consider a toy model no temperature-dependent screening  no modification of the 1S properties - use PDG  melting of 2S and 3S states  melting of the 1P state  continuum threshold s 0 reduction  1S 2S3S T = 0 T  T c  1P1P1P1P ÁM hep-ph/0606124 s0s0s0s0 s0s0s0s0 s0s0s0s0 s0s0s0s0

15. Ágnes MócsyQWG Meeting BNL June 27-30 06 15 the toy model cccc  c0  choice of s 0 can reproduce lattice correlators   c unchanged &  c0 increased  compensate for the melting of higher excited states above T c with the decrease of the threshold ÁM 2006

16. Ágnes MócsyQWG Meeting BNL June 27-30 06 16 with nonrelativistic Green’s fct.  maybe works BUT note: “screened” not screened  screening might not be the mechanism governing quarkonia melting t screening >t Q  Q ÁM, P. Petreczky, J. Casalderrey-Solana, in prep. “screened” Cornell potential

17. Ágnes MócsyQWG Meeting BNL June 27-30 06 17 conclusionconclusion  temperature-dependent screened potentials have problems even though 1S can survive and 1P melts  two different analysis of spectral functions and correlators not consistent with lattice QCD  medium modification cannot be described by a simple Debye screening picture  gluo-dissociation effect  finite width  Green’s fct current investigation current investigation

18. Ágnes MócsyQWG Meeting BNL June 27-30 06 18 my thanks to Péter Petreczky Jorge Casalderrey-Solana Dima Kharzeev Helmut Satz

19. Ágnes MócsyQWG Meeting BNL June 27-30 06 19  T << E QQ gluo-dissociation effect discrete states dominate discrete states dominate  ground state unaffected T >T c gluon sector relevant T >T c gluon sector relevant F. Karsch et al 1996 F. Karsch et al 1996 Rate of J/  escape into the continuum D. Kharzeev, L. McLerran, H. Satz 1995 E. Shuryak 1978 G. Bhanot, M.Peskin 1979 binding energy  T >> E QQ screening  continuum dominates  all states get modified