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Roy A. Lacey. What do we learn from Correlation measurements at RHIC. Conjecture of collisions at RHIC :. Courtesy S. Bass. hadronic phase and freeze-out. QGP and hydrodynamic expansion. initial state. pre-equilibrium. hadronization. Motivation. Which observables & phenomena connect
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Roy A. Lacey What do we learn from Correlation measurements at RHIC Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Conjecture of collisions at RHIC : Courtesy S. Bass hadronic phase and freeze-out QGP and hydrodynamic expansion initial state pre-equilibrium hadronization Motivation Which observables & phenomena connect to the de-confined stage? Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Flow correlations provide an important probe Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
bounce DATA (KAOS – Z. Phys. A355(1996); (E895) - PRL 83(1999) 1295 squeeze Prologue Low Energy: Squeeze-out High Energy In-plane Do we understand Flow correlations ? • Pressure Gradients Drive Transverse and Elliptic flow The expected transition Is observed Phys.Rev.Lett.83:1295,1999 Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
“Barometric Sensor”: What information do Flow correlations provide? • Provides reliable estimates of pressure & pressure gradients • Can address questions related to thermalization • Gives insights on the transverse dynamics of the medium • Provides access to the properties of the medium - EOS, sound speed (cs ), viscosity, etc Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Jet Function Correlation Function Remarkable Fact Azimuthal Correlations are derived from Harmonic and di-jet contributions In-plane Out-of-plane Harmonic There are two sources of azimuthal correlations at RHIC ! Azimuthal Correlations Provide Two Direct routes to the Properties of the High Energy Density Matter Created at RHIC Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
PRL87, 052301 (2001) Extrapolation From ET Distributions peripheral collisions Central collisions time to thermalize the system (t0 ~ 0.2 - 1 fm/c) eBjorken~ 5 - 15 GeV/fm3 ~ 35 – 100 ε0 Phase Transition: Reminder High Energy density matter is created at RHIC! The Energy Density is Well Above the Predicted Value for the Phase Transition /crossover ! Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Cu+Cu Preliminary 3-6%, Npart = 100 Cu+Cu Preliminary 3-6%, Npart = 96 Au+Au 35-40%,Npart = 98 Au+Au 35-40%, Npart = 99 Reminder Particle production & system size Un-scaled dN/d PHOBOS Data Particle production is essentially geometry dominated Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Reminder Statistical Model Comparisons of Particle Ratios Hadro-chemistry indicates a single Hadronization Temperature ~ 175 MeV Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Extrapolation From ET Distributions Large Pressure Gradients v2 Detailed integral and differential Measurements now available for Is Thermalization Rapid ? Self quenching Substantial elliptic flow signals should be present for a variety of particle species Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
PHENIX(open symbols): Phys. Rev. Lett. 91, 182301 (2003) STAR preliminary Is Thermalization Rapid ? Large Pressure Gradients are Generated Very Early ! Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
v2 sheet for mesons & Baryons Exquisite Features Due to Radial flow ? Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
(Rapp) Is Thermalization Rapid ? Heavy quark Thermalization ? Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
PHENIX preliminary PHENIX preliminary Is the matter unique? CERES Results are strikingly similar for V2 decreases by ~ 50% from RHIC to SPS Significantly larger pressure (gradients) at RHIC than at SPS Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
PHENIX preliminary Excitation function for differential v2 Apparent saturation of v2 for Possible indication for a soft EOS ! Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Does the Flow follow ideal hydrodynamics ? Non-trivial issue for EOS, viscosity, etc Investigate Hydrodynamic Scaling Relations for the fine structure of v2 Fit Data Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Buda Lund Hydro Model nucl-th/0310040 P ( WHY ? ) System size independence Fine Structure Scaling Note Universal Scaling prediction M. Csańad C. Csörgo et al. Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Hydro Limit The shape of things to come Scaling Tests Eccentricity scaling Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling of azimuthal anisotropy - Mesons PHENIX Preliminary PHENIX Preliminary • Scaling works over a broad range for charged hadrons and identified particles Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling of azimuthal anisotropy - Hydro Hydro eccentricity scaling Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling of azimuthal anisotropy - system size PHENIX Preliminary Scaling of Cu+Cu and Au+Au collisions indicate system size indipendece Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling PHENIX Data PHENIX Preliminary 5<Centrality<30 % • Unequivocal scaling at low values • scaling breaks ~ 1.8 Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling of azimuthal anisotropy - hadrons Integral flow scaling observed across Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling of RHIC data • Demonstration of higher harmonic scaling Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling breaks Scaling of RHIC data • Demonstration of Comprehensive scaling at RHIC Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
STAR preliminary 200 GeV Au+Au Quark number scaling -- Partonic Flow ? baryons Ξ+Ξ Ω+Ω mesons 200 GeV Au+Au Hadronic re-scattering does not support observed Phi flow ! Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Extended Fine Structure scaling PHENIX Preliminary 5<Centrality<30 % All Flow Data Now Understood Universal scaling prediction! Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Scaling of azimuthal anisotropy - Hydro Estimate cs ! Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
Initial Foray • Fits to the data can provide estimates of the properties of the produced matter Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005
High Density Thermalized partonic material formed early y Hard Scattered Partons Traverse rapidly expanding partonic material Jet-modification (early) & v2 x Epilogue Correlation measurements give compelling evidence for the production of strongly interacting high energy density partonic matter in RHIC collisions. sQGP Roy A. Lacey, Stony Brook, ISMD, Kromĕříž, 2005