Transcript 探索新物质形态—— 夸克胶子等离子体

Recent Progress in the Study on
Quark Matter and Its Realization in Heavy Ion Collisions
庄鹏飞 (清华大学)
高能物理大会，南昌2010
沉痛悼念和怀念刘连寿教授
QCD Phase Transitions and Relativistic Heavy Ion Collisions
FAIR U+U@Elab = 40A GeV
RHIC Au+Au@√s = 200A GeV
deconfinement,
chiral symmetry restoration,
color superconductivity,
pion superfluidity, ……
CSR U+U@Elab = 0.6A GeV
STAR合作组中国成员：
清华大学
中国科技大学
华中师范大学
山东大学
上海应用物理所
兰州近代物理所
LHC Pb+Pb@√s = 5.5A TeV
Strongly Coupled Quark Matter
pair dissociation line
sQGP
BEC
BCS
lattice 2009:
more non-perturbative when charm quark
is thermalized, 50% contribution !
Point:
the validity of a weak coupling expansion
depends not only on the strength of the
coupling, but also on the number of
active degrees of freedom !
CBS  3
BS  B S
S
2
 S
2
 3
BS
S2
Conclusion: two possible sQGP states:
a) independent quasi-partons
b) partons + bound states
● lattice 2009:
T
QCD at High Density
● BCS-BEC crossover in QCD
searching for the QCD critical
● point in canonical ensemble
nB
QCD
cold atoms
● does the
quarkyonic matter
exist in real world
with Nc=3 and what
is the measurable
consequence of the
quarkyonic matter ?
He and Zhuang, PRD2007,2008,2009
● D.Son:
no deconfinement in isospin matter
due to pion superfluidity, even at
extremely high isospin density
● Fridel oscillation at high density
王群,等 PRD2008
QCD at high temperature and density:
刘玉鑫,宗红石,陈继胜,彭光雄,…
AdS/CFT Correspondence
weak coupling in gravity theory corresponds to strong coupling in gauge theory
Kovtun, Son, Starinets, PRL94, (2005)111601:

Bulk viscosity
黄梅,等 PRD2008,2009
1

s 4
pQCD
lattice
AdS/CFT
Conclusion:
minimal  / s and maximum  / s
at the critical point, a possible way
to pinpoint the location of a QCD
phase transition
重夸克介子的熔解温度
侯德富,等 JHEP2008, 2009
Problems:
CFT is not QCD, the coupling constant in AdS/CFT does not run, …
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Signals of QGP Produced in Heavy Ion Collisions
Jet quenching: (王恩科,…)
喷注在热密物质中损失能量
Collective flow: (马余刚,刘峰,…)
体系的膨胀会产生集体流
strong fluctuations: (吴元芳,…)
在QCD临界点附近
J/ψ Suppression: (唐泽波,许晓明,…)
热密物质中有Debye屏蔽
Electromagnetic Signals: (周代翠,…)
电磁信号是最干净的信号
Strangeness enhancement: (杨纯斌,陈列文,…)
QGP中奇异夸克成对产生
Local Parity Violation:
高温高密时对称性自发破缺
Signals from RHIC
Jet quenching
NCQ-scaling
STAR

Large v2

models
Large radial flow
Jet quenching
a matter at parton level at RHIC !
Local Parity Violation
Lee and Wick (PRD1973,1974):
spontaneous P and T violation at high temperature
Kharzeev (PRL1998, PLB2006):
P-odd bubbles in deconfined QCD vacuum with Θ-term


2 
a
g
F
F
a

32 2
  x , t   0 in the bubbles
possible realization in non-central heavy ion collisions:
3 Puzzles in Heavy Ion Collisions (QM2009)
1)DLS Puzzle
low-mass dilepton enhancement,
partial chiral restoration?
A challenge for CSR!
E=1 A GeV
3) J/Psi puzzle:
RAA (|y|<0.35) > RAA (1.2<|y|<2.2)
RAA (RHIC, |y|<0.35) ≈ RAA (SPS)
2)HBT Puzzle
fireballs at SPS and RHIC have
almost the same size !
J/Psi Production at RHIC and LHC
Liu, Yan, Xu, Zhuang, PRL2006, PLB2009
J/Ψ suppression in hot matter (Matsui and Satz, 1986)
Our approach:
J/Ψ transport equation with QCD gluon dissociation
+ relativistic hydrodynamic equations
+ QCD equation of state
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Partonic Wind at RHIC and LHC
Zhu, Xu, Zhuang, PLB2007, PRL2008
DD angular correlation is a sensitive probe of sQGP:
NN collisions: back-to-back correlation
RHIC: almost no correlation
LHC: near-side correlation
c quark motion in QGP:
we take drag coefficient as
a parameter charactering
the coupling strength
QGP evolution:
ideal hydrodynamics
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Outlook
实验
SPS: 达到了产生QGP的条件
RHIC: 发现了产生QGP的一些信号
LHC: Properties of QGP
FAIR,NICA,RHIC energy scan: QCD critical point
CSR: Chiral symmetry restoration
理论
非微扰强相互作用多体问题难度很大
QCD at high density
Strongly coupled quark matter RHIC
Sensitive QGP signatures
谢谢 ！
Compact
Stars
BCS-BEC
AdS/CFT
QGP
Early
Universe
Lattice
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