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Title: Behavior of physical observables in the vicinity of the QCD critical end point

Abstract

Using the SU(3) Nambu-Jona-Lasinio (NJL) model, we study the chiral phase transition at finite T and {mu}B. Special attention is given to the QCD critical end point (CEP): the study of physical quantities, as the pressure, the entropy, the baryon number susceptibility and the specific heat near the CEP, will provide complementary information concerning the order of the phase transition. We also analyze the information provided by the study of the critical exponents around the CEP.

Authors:
 [1]
  1. Centro de Fisica Teorica, Departamento de Fisica, Universidade, P3004-516 Coimbra (Portugal)
Publication Date:
OSTI Identifier:
21056824
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 892; Journal Issue: 1; Conference: QCHS7: 7. conference on quark confinement and the hadron spectrum, Ponta Delgada, Acores (Portugal), 2-7 Sep 2006; Other Information: DOI: 10.1063/1.2714387; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BARYON NUMBER; CHIRAL SYMMETRY; CHIRALITY; ENTROPY; PHASE TRANSFORMATIONS; QUANTUM CHROMODYNAMICS; SPECIFIC HEAT; SU-3 GROUPS

Citation Formats

Costa, Pedro. Behavior of physical observables in the vicinity of the QCD critical end point. United States: N. p., 2007. Web. doi:10.1063/1.2714387.
Costa, Pedro. Behavior of physical observables in the vicinity of the QCD critical end point. United States. doi:10.1063/1.2714387.
Costa, Pedro. Tue . "Behavior of physical observables in the vicinity of the QCD critical end point". United States. doi:10.1063/1.2714387.
@article{osti_21056824,
title = {Behavior of physical observables in the vicinity of the QCD critical end point},
author = {Costa, Pedro},
abstractNote = {Using the SU(3) Nambu-Jona-Lasinio (NJL) model, we study the chiral phase transition at finite T and {mu}B. Special attention is given to the QCD critical end point (CEP): the study of physical quantities, as the pressure, the entropy, the baryon number susceptibility and the specific heat near the CEP, will provide complementary information concerning the order of the phase transition. We also analyze the information provided by the study of the critical exponents around the CEP.},
doi = {10.1063/1.2714387},
journal = {AIP Conference Proceedings},
number = 1,
volume = 892,
place = {United States},
year = {Tue Feb 27 00:00:00 EST 2007},
month = {Tue Feb 27 00:00:00 EST 2007}
}
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  • The presence of a critical end point in the QCD phase diagram can deform the trajectories describing the evolution of the expanding fireball in the {mu}{sub B}-T phase diagram. If the average emission time of hadrons is a function of transverse velocity, as microscopic simulations of the hadronic freezeout dynamics suggest, the deformation of the hydrodynamic trajectories will change the transverse velocity ({beta}{sub T}) dependence of the antiproton-to-proton ratio when the fireball passes in the vicinity of the critical end point. An unusual {beta}{sub T}-dependence of the p-bar/p ratio in a narrow beam energy window would thus signal the presencemore » of the critical end point.« less