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Ágnes Mócsy

AM. Can Quarkonia Survive Deconfinement?. July 16th-19th , 2007 McGill University, Montréal, Canada. July 2007 Early Time Dynamics Montreal. Ágnes Mócsy. Motivation. revisit how we got to “J/  survives up to 2T c ”

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Ágnes Mócsy

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  1. AM Can Quarkonia Survive Deconfinement? July 16th-19th, 2007 McGill University, Montréal, Canada July 2007 Early Time Dynamics Montreal Ágnes Mócsy

  2. Motivation

  3. revisit how we got to “J/ survives up to 2Tc” • from the same data get very different conclusion offering new direction in which models can be modified In this talk

  4. a more detailed motivation

  5. V(r) confined J/ deconfined r • Quarkonium properties at high T interesting • proposed signal of deconfinement Matsui,Satz, PLB 86 • matter thermometer ?! Karsch,Mehr,Satz, ZPhysC 88 • bound states in deconfined medium ?! Shuryak,Zahed PRD 04 The Matsui-Satz argument: Debye screening in the deconfined matter leads to quarkonium dissociation when rDebye rQuarkonium quarkonium discussed in terms of potential model Introduction

  6. Quarkonium properties at high T interesting • proposed signal of deconfinement Matsui,Satz, PLB 86 • matter thermometer ?! Karsch,Mehr,Satz, ZPhysC 88 • bound states in deconfined medium ?! Shuryak,Zahed PRD 04 RBC-Bielefeld Collaboration 2007 Static quark-antiquark free energy Nf=2+1 Screening seen in lattice QCD see talk by Péter Petreczky Introduction

  7. Hierarchy in binding energies c(1P) J/(1S) ’(2S) b’(2P) b(1P) ’’(3S) (1S) 0.4 fm 0.9 fm 0.7 fm 0.2 fm T Quarkonia melting as QGP thermometer • Quarkonium properties at high T interesting • proposed signal of deconfinement Matsui,Satz, PLB 86 • matter thermometer ?! Karsch,Mehr,Satz, ZPhysC 88 • bound states in deconfined medium ?! Shuryak,Zahed PRD 04 Introduction

  8. Quarkonium properties at high T interesting • proposed signal of deconfinement Matsui,Satz, PLB 86 • matter thermometer ?! Karsch,Mehr,Satz, ZPhysC 88 • bound states in deconfined medium ?! Shuryak,Zahed PRD 04 • Need to calculate quarkonium spectral function • quarkonium well defined at T=0, but can broaden at finite T • spectral function contains all information about a given channel • unified treatment of bound states, threshold, continuum • can be related to experiments Introduction

  9. Conclusion: 1S ground state survives above TC Lattice Spectral Functions Asakawa, Hatsuda, PRL 04 see talk by Péter Petreczky Datta et al PRD 04 Jakovác et al, PRD 07 Aarts et al hep-lat/0705.2198 “J/ survival” in LQCD

  10. large uncertainties • not directly measured • extracted from correlators through MEM Lattice Spectral Functions Asakawa, Hatsuda, PRL 04 see talk by Péter Petreczky Datta et al PRD 04 Jakovác et al, PRD 07 Aarts et al hep-lat/0705.2198 “J/ survival” in LQCD

  11. Temperature dependence of correlators c G/Grec 1 implies modified spectral function Jakovác et al, PRD 07 • Conclusions drawn from analysis of lattice data were • c melts by 1.1 Tc • based on modification of G/Grec and spectral functions from MEM “J/ survival” in LQCD

  12. Temperature dependence of correlators ? G/Grec= 1 implied unchanged spectral function c c Jakovác et al, PRD 07 Jakovác et al, PRD 07 • Conclusions drawn from analysis of lattice data were • c melts by 1.1 Tc • J/ and c survive up to 1.5-2Tc “J/ survival” • based on (un)modification of G/Grec and spectral functions from MEM “J/ survival” in LQCD

  13. series of potential model studies • Conclusions • states survive • dissociation temperatures quoted • agreement with lattice is claimed Shuryak,Zahed PRD 04 Wong, PRC 05 Alberico et al PRD 05 Cabrera, Rapp 06 Alberico et al PRD 07 Wong,Crater PRD 07 Wong,Crater, PRD 07 “J/ survival” in Potential Models

  14. Strong screening of Q and antiQ interaction seen on lattice yet some quarkonium states still survive unaffected?

  15. T Tc T = 0 simplified spectral function: discrete bound states + perturbative continuum Mócsy,Petreczky EJPC 05 Mócsy,Petreczky PRD 06 model lattice also Cabrera, Rapp 06 Correlators calculated in this approach do not agree with lattice It is not enough to have “surviving state” First Indication of Inconsistency

  16. What is the source of these inconsistencies? • validity of potential models? • finding the right potential? • relevance of screening for quarkonia dissociation?

  17. our recent approach to determine quarkonium properties Á. Mócsy, P. Petreczky 0705.2559 [hep-ph] 0706.2183 [hep-ph]

  18.  (GeV)  bound states/resonances &  continuum above threshold PDG 06  ~ MJ/ , s0 nonrelativistic medium effects - important near threshold re-sum ladder diagrams first in vector channel Strassler,Peskin PRD 91 also Casalderrey-Solana,Shuryak 04 S-wave nonrelativistic Green’s function P-wave S-wave also Cabrera,Rapp 07 Spectral Function

  19.  (GeV) +  bound states/resonances &  continuum above threshold PDG 06 PDG 06  ~ MJ/ , s0 nonrelativistic   s0 perturbative nonrelativistic Green’s function Spectral Function

  20.  (GeV) +  bound states/resonances &  continuum above threshold PDG 06  ~ MJ/ , s0 nonrelativistic   s0 perturbative smooth matching details do not influence the result nonrelativistic Green’s function + pQCD Unified treatment: bound states, threshold effects together with relativistic perturbative continuum Spectral Function

  21. Phenomenological potential constrained by lattice data Free energy - contains negative entropy contribution - provides a lower limit for the potential Potential assumed to share general features with thefree energy strong screening effects no temperature effects subtract entropy also motivated by Megías,Arriola,Salcedo PRD07 Constructing the Potential at T>Tc

  22. quarkonia in a gluon plasma (quenched QCD)

  23. lattice Jakovác,Petreczky, Petrov,Velytsky, PRD07 Mócsy, Petreczky 0705.2559 [hep-ph] • higher excited states gone • continuum shifted • 1S becomes a threshold enhancement c • resonance-like structures disappear already by 1.2Tc • strong threshold enhancement • contradicts previous claims S-wave Charmonium in Gluon Plasma

  24. Mócsy, Petreczky 0705.2559 [hep-ph] details cannot be resolved • resonance-like structures disappear already by 1.2Tc • strong threshold enhancement above free case indication of correlation • height of bump in lattice and model are similar S-wave Charmonium in Gluon Plasma

  25. N.B.: 1st time 2% agreement between model and lattice correlators for all states at T=0 and T>Tc Unchanged LQCD correlators do not imply quarkonia survival: Lattice data consistent with charmonium dissolution just above Tc Mócsy, Petreczky 0705.2559 [hep-ph] LQCD measures correlators spectral function unchanged across deconfinement or… integrated area under spectral function unchanged S-wave Charmonium in Gluon Plasma

  26. Jakovác et al, PRD 07 b “the b puzzle” b same size as the J/, so why are the b and J/ correlators so different ? P states

  27. constant contribution in the correlator at finite T so look at the derivative following Umeda 07 quark number susceptibility 1.5 Tc c b • Threshold enhancement in spf compensates for dissolution of states • Agreement with lattice data for scalar charmonium and bottomonium Agreement for P-wave as well

  28. charm 1.5 Tc in free theory bottom 1.5 Tc >> deconfined confined  b “puzzle” resolved behavior explained using ideal gas expression for susceptibilities: indicates deconfined heavy quarks carry the quark-number at 1.5 Tc P-wave

  29. quarkonia in a quark-gluon plasma (full QCD)

  30. c  • J/, c at 1.1Tc is just a threshold enhancement • (1S) survives up to ~2Tc with unchanged peak position, • but reduced binding energy • Strong enhancement in threshold region - Q and antiQ remain correlated S-wave Quarkonium in QGP

  31. upper limits on dissociation temperatures

  32. Find upper limit for binding need strongest confining effects = largest possible rmed distance where deviation from T=0 potential starts rmed = distance where exponential screening sets in NOTE: uncertainty in potential - have a choice for rmed or V∞ our choices physically motivated all yield agreement with correlator data Most Binding Potential

  33. strong binding weak binding • When binding energy drops below T • state is weakly bound • thermal fluctuations can destroy the resonance Upsilon remains strongly bound up to 1.6Tc Other states are weakly bound above 1.2Tc Binding Energy Upper Limits

  34. Rate of escape into the continuum due to thermal activation = thermal width  related to the binding energy Kharzeev, McLerran, Satz PLB 95 for weak binding Ebin<T for strong binding Ebin>T Thermal Dissociation Widths

  35. Upper bounds on dissociation temperatures condition: thermal width > 2x binding energy Can Quarkonia Survive?

  36. Quarkonium spectral functions can be calculated within a potential model • with screening - description of quarkonium dissociation at high T • Lattice correlators have been explained correctly for the 1st time • Unchanged correlators do not imply quarkonia survival: • lattice data consistent with charmonium dissolution just above Tc • Contrary to previous statements, we find that all states except  • and b are dissolved by at most by ~1.3Tc • Threshold enhancement found: spectral function enhanced over free propagation =>> correlations between Q-antiQ may remain strong • Outlook • Implications for heavy-ion phenomenology need to be considered • see also Laine,hep-ph/0704.1720 • Brau,Buisseret,hep-ph/0706.4012 Conclusions

  37. ****The END****

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