310 likes | 539 Views
Workshop on RHIC Physics and CSR Physics at Weihai. QCD Phase Diagram in Polyakov-NJL Model. Wei-jie Fu ITP, Chinese Academy of Science August 11, 2009. Outline. Introduction The PNJL Model Numerical Results Inhomogeneous Phases Summary. Introduction.
E N D
Workshop on RHIC Physics and CSR Physics at Weihai QCD Phase Diagram in Polyakov-NJL Model Wei-jie Fu ITP, Chinese Academy of Science August 11, 2009
Outline • Introduction • The PNJL Model • Numerical Results • Inhomogeneous Phases • Summary
Introduction • A semiquantitative QCD phase diagram • In term of temperature and density (chemical potential) • Experiments and observations: RHIC (temperature), Compact stars (density). The Frontiers of Nuclear Science, A Long Range Plan 2007
QCD critical point • Phenomenological Models • Lattice Simulations 1. Reweighting 2. Imaginary chemical potential 3.Taylor expansion 4……. M. A. Stephanov, PoS, LAT2006, 024, 2006
An example: Taylor Expansion C. R. Allton et al., PRD. 71, 054508, 2005
Does the QCD critical point really exist? O. Philipsen, arXiv: 0808.0672, 2008
The PNJL Model • The 2+1 flavor NJL model with a Polyakov-loop is given by where
is the Polyakov-loop effective potential, which is as function of the Polyakov-loop • Two kinds of Polyakov-loop effective potential and
The other is and The Polyakov-loop effective potential as function of the real part and the imaginary part of the Polyakov-loop at two values of the temperature:
Phase Transition at Finite Temperature and Nonzero Chemical Potential
Phase Diagram (Effects of Flavor-mixing and Quark Current Mass) Wei-jie Fu, Zhao Zhang, Yu-xin Liu., PRD. 77, 014006, 2008
Mesonic Excitations at Finite Temperature Schematic representation of the effective interaction for the pseudoscalar modes in the RPA.
The pseudoscalar polarization function is and the scalar polarization function is
Goldberger-Treiman(GT)relation on the quark level at finite temperature: • Gell-Mann--Oakes--Renner (GOR)relation at finite temperature:
Several critical temperatures Wei-jie Fu, Yu-xin Liu., PRD. 79, 074011, 2009
The effect of color confinement screens the effect of temperature below the critical temperature
Inhomogeneous Phases D. Nickel,arXiv: 0906.5295, 2009
Summary • The QCD phase diagram is calculated in the 2+1 flavor PNJL model. We have also investigated the dependence of the location of the QCD critical point on the strength of the ’t Hooft flavor-mixing interaction and the current mass of strange quarks. • Mesonic excitations is studied in the PNJL model. We find that the effect of color confinement screens the effect of temperature below the critical temperature. • Could the Polyakov dynamics affect the inhomogeneous phases, and how? Thank you !