SPC perspective on USQCD thermodynamics Peter Petreczky, BNL - - PowerPoint PPT Presentation

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SPC perspective on USQCD thermodynamics Peter Petreczky, BNL Strategic goals outlined in 2013 White Tools : LQCD, Heavy ion experiments paper, Computational Challenges in QCD and phenomenology Thermodynamics: LQCD results models

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SPC perspective on USQCD thermodynamics

Peter Petreczky, BNL

USQCD All Hands Meeting, FNAL, May 1-2, 2015

Tools : LQCD, Heavy ion experiments and phenomenology LQCD results → models of dynamical evolution → RHIC experiments Strategic goals outlined in 2013 White paper, “Computational Challenges in QCD Thermodynamics”: 1) EoS at zero chemical potentials in the continuum limit ⇒ Hydro models in HIC at top energies ✓ 2) EoS at non-zero chemical potentials, fluctuations of conserved charges ⇒ Freezout condition in HIC, BES@RHIC 3) Universal properties of the chiral transition, Tc(µ) Freezout condition in HIC, BES@RHIC 4) In-medium hadron properties ⇒ dileptons/quarkonia

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high temperature QCD weak coupling ? EM and heavy

flavor probes

Chiral transition, Tc fluctu- ations of conserved charges test of Hadron Resonance Gas (HRG) using LQCD

Physics of heavy ion collisions and LQCD

quarkonium spectral functions, heavy quark diffusion, thermal dileptons EoS

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Structure of thermo LQCD community and USQCD proposals

USQCD proposals in 2015 (time requested in M J/psi core h and GPU node h) :

HotQCD (PI Karsch) Fluctuations : ALCF, zero priority 20%; Titan, 62.5M (15% of INCITE) BNL (PI P. Petreczky) Transition temperature for µB>0 : Clusters, 57.3M (14%) BNL (PI S. Mukherjee) EoS at µB>0 : GPUs 2.48M GPU hours (31%) BNL (PI H.-P. Schadler) High-T QNS: Clusters, 8.67M (2%) MILC (HEP) staggered thermo

non- USQCD resources

BNL (NP) USQCD resources non-USQCD resources

HotQCD

USQCD non-USQCD resources

LANL & LLNL International partners: Bielefeld University

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✏c ' 300MeV/fm3

✏low ' 180MeV/fm3 ✏high ' 500MeV/fm3 ✏proton ' 450MeV/fm3

✏nucl ' 150MeV/fm3

Equation of state at zero baryon density

Hadron resonance gas (HRG): Interacting gas of hadrons = non-interacting gas of hadrons and hadron resonances ( virial expansion, Prakash & Venugopalan ) HRG agrees with the lattice for T< 145 MeV Bazavov et al, PRD90 (2014) 094503

3p/T4 /T4 3s/4T3 4 8 12 16 130 170 210 250 290 330 370 T [MeV]

HRG non-int. limit Tc

(-3p)/T4 T [MeV]

HRG

N=8 N=10 N=12 cont 1 2 3 4 130 170 210 250 290 330 370

Tc = (154 ± 9)MeV

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QCD thermodynamics at non-zero chemical potential

Taylor expansion : Taylor expansion coefficients give the fluctuations and correlations of conserved charges, e.g.

can be done very efficiently on GPUs BNL-BI proposal (PI: PP) HotQCD proposal (PI: Karsch)

BES @ RHIC and freezout conditions

0.2 0.4 0.6 0.8 1 1 2 3 4 5 6 7 8

µB/T0 T/T0

m=o

LGT, m=0, O(µ2)

HRG RHIC 200 GeV RHIC 39 GeV RHIC 7.7 GeV Tf: J.Cleymans et. al.

Need large Nτ

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Equation of state at zero baryon density

Proposal by BNL-BI (PI:Mukherjee) Need high statistics but can be done for smaller Nτ

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What is the transition temperature ?

Zero net baryon density, HotQCD:

Bazavov et al, Phys. Rev. D85 (2012) 054503

K = 2κq, κqs, κs

Curvature parameters are determined by the mixed susceptibility and scaling relation

Non-zero baryon density:

H = mq/ms, h = H/h0, t = (T − Tc)/Tc/t0

Current estimates of the curvature do not agree:

0.059(5) (p4, scaling, BI-BNL, 2010), 0.059(18) (stout, Taylor, WB2011),

0.162(4) (HISQ, imag. µ, Cea et al, 2014), 0.117(27) (stout, imag. µ, Bonatti et al)

t = 1 t0 @T − Tc Tc + X

i,j

µiµj T 1 A

Phenomenological Freezout curve: ~ 0.21(2)

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Quark number fluctuations at high T

At high temperatures quark number fluctuations can be described by weak coupling approach due to asymptotic freedom of QCD

Good agreement between lattice and the weak coupling approach for 2nd order

quark number fluctuations

For 4th order no continuum results => proposal by Schadler

2nd order quark number fluctuations

4th order quark number fluctuations T [MeV] q

2/SB 2

3d pert. NLA 0.9 0.91 0.92 0.93 0.94 0.95 0.96 0.97 0.98 300 400 500 600 700 800 900 1000 T [MeV] q

4/SB 4

LO HTLpt 3d pert. N=6 N=8 N=12 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 300 400 500 600 700 800 900 1000

EQCD

Bazavov et al, PRD88 (2013) 094021

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In-medium meson properties

No proposals this year on but progress is being made using configurations generated by HotQCD are being used for study meson spectral functions: Bazavov et al, Phys.Rev. D91 (2015) 5, 054503 Bazavov, Burnier, PP, arXiv:1404.4267 Kim, PP, Rothkopf, Phys.Rev. D91 (2015) 054511

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Conclusions

Lattice QCD starts to provide quantitative results that provide important input for interpreting the experimental results from HIC Main focus: Tc, EoS, fluctuation of conserved charges at non-zero baryon density => RHIC BES II program SPC: When the results are needed ? They were due yesterday ! BES II is likely to happen in 2019/2020, phenomenological modeling is in progress and need input from lattice QCD now ⇒ BEST Topical Collaboration (PI : S. Mukherjee) In-medium meson properties (some progress) Relevant for heavy flavor program at RHIC (STAR upgrade, sPHENIX, ALICE, CMS) ⇒ Topical Collaboration for Heavy Flavor Probes of QGP (PI : R. Rapp, co-PI, P. Petreczky)