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Ágnes Mócsy at RBRC
1
TIFR Mumbai India Feb 12-14 2008
Quarkonium as Signal of Deconfinement
Ágnes MócsyÁgnes MócsyQuickTime™ and a
TIFF (Uncompressed) decompressorare needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
Thanks to Sourendu, Saumen, Rajeev, Rajiv!Thanks to Sourendu, Saumen, Rajeev, Rajiv!
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
In this talk:In this talk:
• Why quarkonium at finite T interesting
• Initial interpretation of quarkonium lattice data
• Results from potential model. Comparison to lattice
• Upper limit binding energies. Estimates of upper
limit dissociation T
• Comments on the potential
• Conclusions
based on Á. Mócsy, P. Petreczky Phys. Rev. D 77, 014501 (2008)
Phys. Rev. Lett. 99, 211602 (2007)
based on Á. Mócsy, P. Petreczky Phys. Rev. D 77, 014501 (2008)
Phys. Rev. Lett. 99, 211602 (2007)
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
can signal QGP formation in heavy ion collisionsMatsui and Satz (1986)
Screening in deconfined matter weakens potential (force) between heavy quark and antiquark.
Color ScreeningColor Screening J/ meltingJ/ melting
confined
deconfinedJ/
r
V(r)
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
can signal QGP formation in heavy ion collisionsMatsui and Satz (1986)
Screening in deconfined matter weakens potential (force) between heavy quark and antiquark.
Strong screening seen in Lattice Strong screening seen in Lattice
RBC-Bielefeld Collab.
(2007)
Free energy of a static Q-Qbar in Nf=2+1
Color ScreeningColor Screening J/ meltingJ/ melting
Poster by K.Petrov Poster by K.Petrov
With increasing T screening sets in at shorter and shorter distances
With increasing T screening sets in at shorter and shorter distances
Model independent statement Range of interaction between Q and Qbar is strongly reduced
Model independent statement Range of interaction between Q and Qbar is strongly reduced
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
can signal QGP formation in heavy ion collisionsMatsui and Satz (1986)
RBC-Bielefeld Collab.
(2007)
Free energy of a static Q-Qbar in Nf=2+1
Color ScreeningColor Screening J/ meltingJ/ melting
QGP thermometer QGP thermometer
T/TC 1/r [fm-1]
(1S)
J/(1S)
c(1P)
’(2S)
b’(2P)
’’(3S)
With increasing T screening sets in at shorter and shorter distances
With increasing T screening sets in at shorter and shorter distances
Strong screening seen in Lattice Strong screening seen in Lattice Model independent statement Range of interaction between Q and Qbar is strongly reduced
Model independent statement Range of interaction between Q and Qbar is strongly reduced
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
can signal QGP formation in heavy ion collisionsMatsui and Satz (1986)
J/ suppression measured at SPS and RHIC
J/ suppression measured at SPS and RHIC
Color ScreeningColor Screening J/ meltingJ/ melting
QGP thermometer QGP thermometer
T/TC 1/r [fm-1]
(1S)
J/(1S)
c(1P)
’(2S)
b’(2P)
’’(3S)
Must know quarkonia properties, dissociation temperatures!Must know quarkonia properties, dissociation temperatures!
NA50 at SPS (0<y<1)PHENIX at RHIC (|y|<0.35)
Bar: uncorrelated errorBracket : correlated errorGlobal error = 12% is not shown
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Potential ModelsLattice QCD
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Spectral Functions Extracted from Lattice Spectral Functions Extracted from Lattice
Common interpretation: 1S ground state survives (unaffected) well above TC
Common interpretation: 1S ground state survives (unaffected) well above TC
c
Would the J/ survive unaffected in the QGP up to 1.5-2Tc even though strong screening is
present ?
Would the J/ survive unaffected in the QGP up to 1.5-2Tc even though strong screening is
present ?
Jakovác,Petreczky,Petrov,Velitsky PRD (2007)
Started an avalanche of new potential model works to explain J/ survival Digal et al,Shuryak,Zahed,Blaschke,Wong, Rapp, Alberico,Manarelli, Cabrera, …
Unified treatment of bound-, scattering states, threshold effectsAsakawa, Hatsuda, Umeda, Datta et al, Iida, Jakovac et al, Aarts et al …
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Euclidean-time Correlators Euclidean-time Correlators
€
G τ ,T( ) = σ ω,T( )K τ ,ω,T( )dω∫
€
Grec τ ,T( ) = σ ω,T = 0( )K τ ,ω,T( )dω∫
3. In ratio lattice artifacts understood - Mócsy, Petreczky EJP 2007
€
G τ ,T( ) = σ ω,T( )K τ ,ω,T( )dω∫
to answer, Look at
1. Numerical results more reliable - directly measured on the LatticeBecause:
CorrelatorMEASURED
Spectral Function
EXTRACTED with MEM
Kernel cosh[(-1/2T)]/sinh[/2T]
2. Ratio of correlators eliminates trivial T-dependence of K
Mócsy, Petreczky PRD 2005
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Initial interpretation:
€
G τ ,T( ) = σ ω,T( )K τ ,ω,T( )dω∫
€
Grec τ ,T( ) = σ ω,T = 0( )K τ ,ω,T( )dω∫ 1spectral function modified,state melts
= 1 spectral function unchanged, state survives
J/(c) survives up to 1.5-2Tc and c melts by 1.1 Tc has been reported
Potential models must be checked for agreement with lattice data on correlators as wellPotential models must be checked for agreement with lattice data on correlators as well
calculate in potential model
compare to
lattice data
c
Datta et al PRD 04
c
Datta et al PRD 04
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
in contradiction with statements made in the literature
Correlator at T=0
Correlator at T=0
Relativistic continuum seen on the lattice
Relativistic continuum seen on the lattice
Mócsy, Petreczky, PRD 08
Non-relativistic continuum
Relativistic continuum
Lattice data from Datta et al, PRD 05
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Potential Model with Nf=0
Potential Model with Nf=0
c
No resonance-like structures at 1.2Tc Seemingly contradicts
previous claims.
No resonance-like structures at 1.2Tc Seemingly contradicts
previous claims.
Near threshold there is an enhancement above free quark
propagation. Indicates correlation.
Near threshold there is an enhancement above free quark
propagation. Indicates correlation.
Pseudoscalar results with potential constrained by lattice free energy data
Threshold enhancement compensates for melting of
states
Threshold enhancement compensates for melting of
states
Lattice data
~ 2%For the First Time Agreement between potential model and lattice correlators to few % and for all states
For the First Time Agreement between potential model and lattice correlators to few % and for all states
Jakovác et al PRD (07)
Lattice data is consistent with J/ melting above Tc
Lattice data is consistent with J/ melting above Tc
Details cannot be resolved Details cannot be resolved
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Constant contribution in the correlator
quark number susceptibility
1.5 Tc
Zero-mode contributionZero-mode
contribution
Threshold enhancement compensates for dissolution of states
Threshold enhancement compensates for dissolution of states
Scalar channel contains low frequency contribution at finite temperature
Bound and unbound Q-Qbar pairs
(>2mQ)
Bound and unbound Q-Qbar pairs
(>2mQ)
Quasi-free heavy quarks interacting with the medium
Quasi-free heavy quarks interacting with the medium
following Umdeda, PRD 07
Zero mode is not present in the derivative of correlator
Dissolution of the c does not lead to large increase in the correlator
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
When Ebin < T, state is waekly bound and thermal fluctuations can destroy it. Do not need to reach the usual Ebin=0 to dissociate a state.
When Ebin < T, state is waekly bound and thermal fluctuations can destroy it. Do not need to reach the usual Ebin=0 to dissociate a state.
Potential constrained by lattice free energy data w. realistic quark masses
Ebin = 2mq+V∞(T)-M distance between peak position and continuum threshold
Spectral function may show resonance-like peak structures but binding energy can be small
Spectral function may show resonance-like peak structures but binding energy can be small
{
Potential Model with Nf=2+1
Potential Model with Nf=2+1
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
€
Ebin < Tweak binding
€
Ebin > Tstrong binding
Binding Energy Upper Limit Binding Energy Upper Limit 1. Use the most confining potential still consistent with full QCD lattice data on static Q-antiQ energies
2. Estimate dissociation rate due to thermal activation (width) Ebin< T following Kharzeev,McLerran,Satz, PLB 953. Ad hoc choice dissociation condition: Thermal width > 2 x Binding energy
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Dissociation Temperatures in QCD Upper Bound estimateDissociation Temperatures in QCD Upper Bound estimate
Mócsy, Petreczky PRL (2007)
Implications for heavy ion phenomenology to consider
• Similarity of J/ RAA at SPS and RHIC?• Upsilon suppression at RHIC?
Calibration of the QGP thermometerCalibration of the QGP thermometer
T/TC 1/r [fm-1]
(1S)
J/(1S) ’(2S)
c(1P) ’(2S)b’(2P) ’’(3S)TC
2
1.2
b(1P)
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
Set of potentials at 1.2Tc
T=0 potential
lattice internal energy
lattice free energy
pseudoscalar
G/Grec from set of potentials all agree with correlator lattice data
G/Grec from set of potentials all agree with correlator lattice data
Comment on the potentialComment on the potential
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
For the first Time agreement is found between a potential model and lattice correlators for all
states
For the first Time agreement is found between a potential model and lattice correlators for all
states
SummarySummary
Lattice data are consistent with J/ dissociation just above Tc
what has changed? Flatness of G/Grec and lattice spectral function peak does not necessarily imply survival, as it was thought before.Increase in correlators is due to different physics, not dissociation. G/Grec are flat in all channels. Indication of Q-Qbar correlation.
Lattice data are consistent with J/ dissociation just above Tc
what has changed? Flatness of G/Grec and lattice spectral function peak does not necessarily imply survival, as it was thought before.Increase in correlators is due to different physics, not dissociation. G/Grec are flat in all channels. Indication of Q-Qbar correlation.
Determined upper limit on binding energies using lattice data on free and internal energy together
with potential model.
Determined upper limit on binding energies using lattice data on free and internal energy together
with potential model. Estimate of upper limit on dissociation temperatures indicate that most states except the and b are
dissolved close to Tc
Estimate of upper limit on dissociation temperatures indicate that most states except the and b are
dissolved close to Tc
Ágnes Mócsy at RBRC
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TIFR Mumbai India Feb 12-14 2008
****The END****