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Quarkonium Properties Above Deconfinement. Zim á nyi 75 MEMORIAL WORKSHOP ON HADRONIC and QUARK MATTER July 2 - 4 (Mon - Wed), 2007 Budapest, Hungary. Ágnes Mócsy. Motivation. revisit how we got to “J/psi survives up to 2T c ” from same data get very different conclusion.
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Zimányi 75 Memorial Workshop, Budapest 07 03 07 Quarkonium Properties Above Deconfinement Zimányi 75 MEMORIAL WORKSHOP ON HADRONIC and QUARK MATTER July 2 - 4 (Mon - Wed), 2007 Budapest, Hungary Ágnes Mócsy
Zimányi 75 Memorial Workshop, Budapest 07 03 07 • revisit how we got to “J/psi survives up to 2Tc” • from same data get very different conclusion offering new direction in which models can be modified Motivation
Zimányi 75 Memorial Workshop, Budapest 07 03 07 a more detailed motivation
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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 Introduction
Zimányi 75 Memorial Workshop, Budapest 07 03 07 • 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 Introduction
Zimányi 75 Memorial Workshop, Budapest 07 03 07 c(1P) J/(1S) ’(2S) b’(2P) b(1P) ’’(3S) (1S) 0.4 fm 0.9 fm 0.7 fm 0.2 fm T Hierarchy in binding energies Quarkonia 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 • 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 Spectral Functions Asakawa, Hatsuda, PRL 04 Jakovác et al, PRD 07 extracted from Datta et al PRD 04 Aarts et al hep-lat/0705.2198 Correlators c c Jakovác et al, PRD 07 Jakovác et al, PRD 07 • Conclusions drawn from analysis of lattice data were • J/ and c survive up to ~1.5-2Tc “J/ survival” • c melts by 1.1 Tc • based on (un)modification of G/Grec and spectral functions from MEM “J/ survival” in LQCD
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 simplified spectral function: discrete bound states + perturbative continuum Mócsy,Petreczky EJPC 05 and PRD 06 T Tc T = 0 model lattice it is not enough to have “surviving state” correlators calculated in this approach do not agree with lattice • What is the source of these inconsistencies? • validity of potential models? • finding the right potential? • relevance of screening for quarkonia dissociation? First Indication of Inconsistency
Zimányi 75 Memorial Workshop, Budapest 07 03 07 our recent approach to determine quarkonium properties Á. Mócsy, P. Petreczky 0705.2559 [hep-ph] 0706.2183 [hep-ph]
Zimányi 75 Memorial Workshop, Budapest 07 03 07 (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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 (GeV) + bound states/resonances & continuum above threshold PDG 06 PDG 06 ~ MJ/ , s0 nonrelativistic s0 perturbative nonrelativistic Green’s function Spectral Function
Zimányi 75 Memorial Workshop, Budapest 07 03 07 (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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 T>0 potential is unknown use a phenomenological potential constrained by lattice data Free energy - contains negative entropy contribution - provides a lower limit for the potential see talk by Péter Petreczky Potential assumed to share general features with thefree energy no temperature effects strong screening effects subtract entropy also motivated by Megías,Arriola,Salcedo PRD07 Constructing the Potential at T>Tc
Zimányi 75 Memorial Workshop, Budapest 07 03 07 quarkonia in a gluon plasma (quenched QCD)
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 details cannot be resolved Mócsy, Petreczky 0705.2559 [hep-ph] • 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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 of spf compensates for dissolution of states • Agreement with lattice data for scalar charmonium and bottomonium Agreement for P-wave as well
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 quarkonia in a quark-gluon plasma (full QCD)
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 upper limits on dissociation temperatures
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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
Zimányi 75 Memorial Workshop, Budapest 07 03 07 Upper bounds on dissociation temperatures condition: thermal width > 2x binding energy Can Quarkonia Survive?
Zimányi 75 Memorial Workshop, Budapest 07 03 07 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 1.3 Tc 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 Conclusions
Zimányi 75 Memorial Workshop, Budapest 07 03 07 ****The END****