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(I): Matter in Extremis. QCD and Heavy Ion Physics. 高能物理前沿暑期论坛 威海 July 31 – August 7 , 2006. Xin-Nian Wang. Lawrence Berkeley National Laboratory. Phases of Matter. 火 水 土. (gas). (liquid). (solid). Bose-Einstein condensate, fermionic condensate,
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(I): Matter in Extremis QCD and Heavy Ion Physics 高能物理前沿暑期论坛 威海 July 31 – August 7, 2006 Xin-Nian Wang Lawrence Berkeley National Laboratory
Phases of Matter 火水土 (gas) (liquid) (solid) Bose-Einstein condensate, fermionic condensate, superfluids, supersolids, paramagnetic, ferromagnetic, liquid crystals, … Quark-gluon Plasma (QGP)
Quark-gluon Plasma (QGP) Discovery of asymptotic freedom of QCD: Gross, Wilczek and Politzer (1973) Weakly interacting quarks at high density and temperature First concept of QGP in early universe, neutron star core and change of the vacuum structure at high temperature Lee and Wick,(1974); Collins and Perry (1975); Baym and Chin (1976)
QCD Theory • SU(3) gauge symmetry (non-Abelian) • Asymptotic freedom at short distance • Confinement at long distance • Scale invariance and anomaly • Chiral symmetry and its spontaneous breaking • Goldstone boson and chiral condensate • UA(1) symmetry and anomaly
Scale Anomaly and invariance at high T Scale anomaly Break scale invariance
SB limit • Quasi-particle with dispersion given by HTL resummation Blaizot, Iancu, Rebhan ‘2001 • Super Yang-Mills Guber, Klebanov, Tseytlin ‘1998 EOS in Lattice QCD F. Karsch ‘2001 25%
J/Y suppression Confinement-deconfinement SU(3) non-Abelian gauge interaction confinement Heavy quark potential: Karsch, Laermann and Peikert 2001
Could there be many other resonances? Shuryak & Zahed ‘04 Resonances in QGP above Tc? Maximum entropy method (MEM) Hatsuda et al Hatsuda et al, 2004 J/Y survives up to T=1.6Tc
f f1 f f2 Cerenkov gluon radiation in near Tc? Koch, Majumder & XNW’05 Dielectric constant
F. Karsch ‘2001 Chiral Symmetry Goldstone bosons (p,K,h) Spontaneously broken:
Quark Matter in Neutron Stars Spin-up Spin-down N. Glendenning ‘2000
Heavy-ion Collisions RHIC BNL Au+Au up to 200 GeV/n
EM emission: Medium response to EM interaction g production, J/Y suppression • Hard probes: Medium response to strong interaction Jet quenching • Soft hadrons: Bulk properties of medium, collective behavior Medium Response Dynamic System:
t Energy Density in Heavy-ion Collisions Above the critical density from lattice QCD
EZDC z x y Impact Parameter (b) ET Centrality of the collisions Non-central Heavy Ion Collisions ET EZDC
Ideal Hydro calculation Pressure gradient anisotropy Elliptic Flow
Constraint on thermalization time Heinz ‘04 Constraint on shear viscosity: Teaney ‘03 H2O : A perfect fluid? Ideal Hydrodynamic
Transport: Kubo relation Shear viscosity Energy-momentum tensor in microscopic picture
? Kapusta, Csernai & McLerran Viscosity of QCD Matter • Hadron gas at low temperature: • Chiral perturbation theory: • QGP at high temperature: • Perturbative QCD Prakash et al Chen & Nakano Arnold, Moore,Yaffe
Small viscosity in SYM Policastro, Son & Starinets ‘02 Phase transition or strong coupling? Is it possible to measure h/s from experiments?
n = number of constituent quarks Quark Coalescence Rec. Models Hwa & Yang Fries, Muller, Bass Ko et al
Bifurcation of Spectra Constituent quark recombination promote baryon production
q Index of refraction Velocity of sound: Shock Wave or Cherenkov Radiation PHENIX
Dx Orbital angular momentum
n p pf xT Quark Polarization Polarized cross section: Zuo-tang Liang & XNW PRL 94(2005)
Au+Au @ 200GeV (20-70%) Au+Au @ 62GeV (0-80%) STAR Preliminary STAR Preliminary (GeV/c)
Summary • Broken symmetries and their restoration at high T accompanied by phase transitions • Intriguing properties of QGP near the critical point • Study of soft hadrons from RHIC experiments: • High initial energy density above Tc reached • Chemical equilibrium at freeze-out • Strong collective flow indicating fluid property with low viscosity • Partonic degree of freedom before hadronization • Many other effects such a global quark polarization provide additional information
(II): Hard Probes of Dense Matter QCD and Heavy Ion Physics 高能物理前沿暑期论坛 威海 July 31 – August 7, 2006 Xin-Nian Wang Lawrence Berkeley National Laboratory
EM emission: Medium response to EM interaction • Hard probes: Medium response to strong interaction Jet quenching Medium Response Dynamic System: • Soft hadrons: Bulk properties of medium, collective behavior
Bjorken’82, XNW & Gyulassy’92 Jets in heavy-ion collisions pQCD leading particle q q leading particle
Absorption properties Compute assisted Correction Calibrated source QGP pQCD p+p, p+A Expansion dynamics dE/dx Jet Tomography
v Final rad. Formation time Initial rad. Landau-Pomeranchuck-Midgal interference LPM interference in EM Radiation EM field carried by a fast moving electron EM Radiation by scattering: Interference between initial and final state radiation
pi pf k QED y 0 pi pf QCD Gluon multiple scattering (BDMP’96) pi pf c k a y 0 Radiation in QCD: Colors matter k
Suppression of leading particles(Huang, XNW’96) (Guo & XNW’00) Modified Jet Fragmentation
e- Frag. Func. DIS off Nuclei
e- Modified frag. function Parton energy loss: A twisted story
Modified fragmentation function Guo & XNW(2000) Quark energy loss pT broadening (Guo’98)
e- Energy Loss in Cold Nuclear Matter Enke Wang & XNW (2000) in Au nuclei
Suppression of away-side jet Initial Density about 30 times of that in a Cold Au Nucleus
q Index of refraction Velocity of sound: Cherenkov radiation or shock wave PHENIX
Ideal quarks Bound state QGP or hadronic gas Gavai & Gupta ‘05 Degrees of freedom in sQGP? Koch, Majumder & Randrup ‘05 • Quark-gluon plasma: • s quark has both B and S • B & S strongly correlated, CBS=1 • Hadron gas: • K meson has B=0 • B-S correlation is more complicated