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Source Imaging Using RHIC Data. Roy A. Lacey. Prospects for locating the QCD Critical End Point (CEP). A Central Question of the Field?. The location of the critical End point and the phase boundaries are fundamental to the QCD phase diagram !. Freeze out Curve. Theoretical Guidance ?.
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Source Imaging Using RHIC Data Roy A. Lacey Prospects for locating the QCD Critical End Point (CEP) Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
A Central Question of the Field? The location of the critical End point and the phase boundaries are fundamental to the QCD phase diagram ! Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Freeze out Curve Theoretical Guidance ? Theoretical Predictions For the CEP Any search for the CEPrequires investigations over a broad range of μ & T. Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
For the first time (at last) we have access to the full range Of μ and T. (via Energy scans at RHIC, SPS & FAIR) Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Better News ! • The Crossover Transition to the QGP is made clear at RHIC • Space-time measurements • Flow Measurements • Jet Quenching The Crossover is a necessary requirement for locating the CEP • 2) Viscosity Measurements offer a new dynamical probe for the CEP • Contrasts Stationary State variables Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Courtesy S. Bass hadronic phase and freeze-out QGP and hydrodynamic expansion initial state pre-equilibrium hadronization The Space-Time probe Puzzle ? Are source Imaging measurements consistent with the crossover transition ? hadronization The space-time extent (Source Image) can lend crucial insights A Cross Over strongly affects the Space-time Dynamics Theory indicate a crossover transition Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Discretize Integral Vary S(rj) to minimize Brown & Danielewicz PRC 57(98)2474 Direct Fit Source function (Distribution of pair separations) Correlation function Encodes FSI Source Imaging Methodology (1D) 1D Koonin Pratt Eqn. Inversion of this integral equation Source Function Reliable measurement of the full 1D Source Function ! Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Expand R(q) and S(r) in Cartesian Harmonic basis (Danielewicz and Pratt nucl-th/0501003) Substitute (2) and (3) into (1) The 3D integral equation is reduced to a set of 1D relations for different l coefficients moments Source Imaging Methodology (3D) 3D Koonin Pratt Eqn. Reliable measurement of the full Source Function in 3D ! Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Correlation Moments PHENIX Data Robust Experimental Source Functions obtained from moments Contributions from l > 6 is negligible Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
The transition is Not a Strong First order Phase Transition? • Therminator: • A.Kisiel et al. Comput.Phys.Commun.174, 669 (2006) • Thermal model with Bjorken longitudinal expansion and transverse Flow • Spectra & yields constrain thermal properties • Transverse radius ρmax : controls • transverse extent • Breakup time in fluid element rest frame, • : controls longitudinal extent • Emission duration : controls tails in • long and out directions • a controls x-t correlations Source Function Comparison to Models Give robust life time estimates Consistent with Crossover transition Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
The Flow Probe From ET Distributions Control Params. Expect Large Pressure Gradients Hydro Flow Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Scaling for identified hadrons Scaling for Phi Mesons Scaling for Heavy Quark Courtesy S. Bass QGP and hydrodynamic expansion hadronic phase and freeze-out initial state pre-equilibrium hadronization Universal Scaling We hold these truths to be self evident ! Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
F. Karsch, hep-lat/0601013 The expected saturation of v2 Is observed Phys.Rev.Lett.94:232302,2005 Saturation of Elliptic flow consistent with a soft EOS associated with Crossover Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
v4/(v2)2 0.5-0.6 1.0 Hexadecapole Flow (v4) As a predictor of Thermalization The prediction for thermalization is explicit and specific Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
PHENIX Preliminary Hexadecapole Flow (v4) As a predictor of Thermalization v4 The prediction for thermalization is explicit and specific Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Scaling for Higher Harmonics Courtesy S. Bass QGP and hydrodynamic expansion hadronic phase and freeze-out initial state pre-equilibrium hadronization The ratio of the harmonics for quarks is compatible with hydrodynamic prediction Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Transport Coefficient Estimates - I Model Comparison 1-2 X the conjectured lower bound Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Transport Coefficient C. Greiner et al Thermalization facilitated by 23 processes Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
High pT trigger Same-Side Jet x10 x20 Setting an upper limit on The viscosity QCD Sonic Boom Gives sound speed directly; Sets upper limit on viscosity. Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
True 3PC jet correlations QCD Sonic Boom? Data Total 3PC jet correlations The data is compatible with the presence of a Mach Cone away-side jet Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
is a potent signal for the CEP CEP Search Lacey et al. arXiv:0708.3512 [nucl-ex] Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Kharzeev-Tuchin Meyer Nonaka et al. is a potent signal for the CEP CEP Search Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Kharzeev-Tuchin Meyer are a potent signals for the CEP How to find the CEP? First estimate T ~ 165-170 μ ~ 120-150 MeV Need two energies immediately Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Epilogue • Strong evidence for crossover to the QGP at RHIC. • Short emission lifetimes • Matter quenches Jets and flows as a (nearly) perfect fluid with systematic patterns consistent with quark degrees of freedom. • Matter has a soft EOS and a shear viscosity to entropy density ratio lower than any other known fluid -- a value close to the conjectured quantum bound • Corresponding bulk viscosity to entropy density is large Extracted Transport Coefficients Suggest Decay Trajectories close to the Critical End Point (CEP) Energy scans now required to do the trick !! First estimate T ~ 165 μ ~ 120 -150 MeV Need two energies immediately Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
v2/ε for <pT> ~ 0.45 GeV/c cs ~ 0.35 ±0.05 (cs2 ~ 0.12), soft EOS F. Karsch, hep-lat/0601013 See nucl-ex/0604011 for details The EOS of the Partonic Fluid is Soft Hydro Calculations (Bhalerao et al.) The EOS is harder than that for the hadron gas but softer than for the hard QGP no strong first order phase transition Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008
A Crossover transition to the strongly coupled thermalized QGP occurs at RHIC Courtesy S. Bass QGP and hydrodynamic expansion hadronic phase and freeze-out initial state pre-equilibrium hadronization We hold these truths to be self evident ! Roy A. Lacey, Stony Brook; 24th Winter Workshop on Nuclear Dynamics, April 5-12, 2008