Quark Matter at High Density/Temperature James Dunlop ICHEP041 Quark Matter at High Density/Temperature James C Dunlop Brookhaven National Laboratory Quark Matter at High Density/Temperature James Dunlop ICHEP042 QGP a (locally) thermally equilibrated state of matter in which quarks and gluons are deconfined from hadrons, so that color degrees of freedom become manifest over nuclear, rather than merely nucleonic, volumes. M. Gyulassy & L. McLerran Approximately thermalized matter at energy densities so large that the simple degrees of freedom are quarks and gluons. This energy density is that predicted by LGT for the existence of a QGP, 2 GeV/fm 3. Defining the question Recent Definition from STAR for the Quark Gluon Plasma Contrast with other recent definition: Quark Matter at High Density/Temperature James Dunlop ICHEP043 RHIC Implementation Flexibility is key to understanding complicated systems Polarized protons, sqrt(s) = GeV Nuclei from d to Au, sqrt(s NN ) = GeV Physics runs to date GeV Polarized GeV 200 GeV PHENIX BRAHMS &PP2PPPHOBOS STAR 1.2 km RHIC Quark Matter at High Density/Temperature James Dunlop ICHEP044 RHIC Experiments Four experiments, two large, two small: STAR: Large acceptance ( PHENIX: Electron/muon identification, high rate trigger, limited acceptance ( central arm) PHOBOS: Tabletop: limited tracking acceptance, largest multiplicity acceptance of all experiments BRAHMS: Forward tracking in classical spectrometer Quark Matter at High Density/Temperature James Dunlop ICHEP045 in entropy density, hence pressure in heavy-quark screening mass in chiral condensate The most realistic calcs. no discontinuities in thermodynamic proper- RHIC conditions (i.e., no 1 st - or 2 nd -order phase transition), but still crossover transition with rapid evolution vs. temperature near T c 160 170 MeV. Lattice QCD Predicts a RAPID Transition Quark Matter at High Density/Temperature James Dunlop ICHEP046 No exptal smoking gun! Rely on theory-expt comparison Charged particle pseudo- rapidity density HBT parameters p T -integrated elliptic flow p T -integrated elliptic flow, scaled by initial spatial eccentricity But only smooth behavior is observed Quark Matter at High Density/Temperature James Dunlop ICHEP047 p T -integrated yield ratios in central Au+Au collisions consistent with Grand Canonical stat. T ch = (160 10) MeV, B 25 MeV, across u, d and s sectors ( s consistent with 1.0). Inferred T ch consistent with T crit (LQCD) T 0 =~ T crit. Does result point to thermodynamic and chemical equilibration, and not just phase-space dominance? Also works in e + e -, p+p Strangeness Enhancement Resonances STAR O PHENIX Chemical Equilibration? Hadron Yield Ratios Quark Matter at High Density/Temperature James Dunlop ICHEP048 Collective Behavior: Azimuthal Anisotropy v 2 y x pypy pxpx coordinate-space-anisotropy momentum-space-anisotropy Pressure converts initial coordinate-space Anisotropy into final momentum-space anisotropy Quark Matter at High Density/Temperature James Dunlop ICHEP049 Time evolution in Ideal Hydrodynamics Elliptic Flow reduces spatial anisotropy -> shuts itself off Sensitive to EARLY TIMES Quark Matter at High Density/Temperature James Dunlop ICHEP0410 Elliptic flow with ultracold trapped Li6 atoms, a=> infinity regime The system is extremely dilute, but can be put into a hydro regime, with an elliptic flow, if it is specially tuned into a strong coupling regime via the so called Feshbach resonance Extremely cold system at T=10 nK or 10^(-12) eV can produce micro-bang Analogy to Ultracold Atoms Analogy pointed out by Shuryak Quark Matter at High Density/Temperature James Dunlop ICHEP0411 Hydro calculations: Kolb, Heinz and Huovinen v 2 vs. Ideal Hydrodynamics Ideal hydrodynamics reproduces v 2 relatively well Below p T ~2 GeV, matches v 2 and spectra to ~20-30% Appealing picture: Nearly perfect fluid with local thermal equilibrium established at 5 GeV/c: suppression ~ independent of p T PRL 91, Au+Au relative to p+p Au+Au central/peripheral R AA R CP Quark Matter at High Density/Temperature James Dunlop ICHEP0418 pQCD in Au+Au? Direct photons [ w/ the real suppression] ( pQCD x N coll ) / background Vogelsang/CTEQ6 [if there were no suppression] ( pQCD x N coll ) / ( background x N coll ) Au+Au 200 GeV/A: 10% most central collisions [ ] measured / [ ] background = measured / background Preliminary Perturbative calculation for direct photons works in central Au+Au p T (GeV/c) Quark Matter at High Density/Temperature James Dunlop ICHEP0419 0 R AA s Systematics Cronin and parton energy loss at lower s Vitev, nucl-th/ Reasonable agreement with 62.4 GeV result. larger Cronin effect gluon dN/dy = 850 (rather than 1100) No large surprises in energy dependence PHENIX Preliminary Quark Matter at High Density/Temperature James Dunlop ICHEP0420 Jets at RHIC p+p jet+jet Au+Au ??? nucleon parton jet Find this.in this Quark Matter at High Density/Temperature James Dunlop ICHEP0421 Jets and two-particle azimuthal distributions p+p dijet trigger: highest p T track, p T >4 GeV/c distribution: 2 GeV/c