Phase transition and nucleon as soliton in the Nambu-Jona-Lasinio model at finite temperature and density

Abstract

We study some bulk thermodynamical characteristics, meson properties and the nucleon as a baryon number one soliton in a hot quark matter in the NJL model as well as in a hot nucleon matter in a hybrid NJL model in which the Dirac sea of quarks is combined with a Fermi sea of nucleons. In both cases, working in mean-field approximation, we find a chiral phase transition from Goldstone to Wigner phase. At finite density the chiral order parameter and the constituent quark mass have a non-monotonic temperature dependence - at finite temperatures not close to the critical one they are less affected than in the cold matter. Whereas the quark matter is rather soft against thermal fluctuations and the corresponding chiral phase transition is smooth, the nucleon matter is much stiffer and the chiral phase transition is very sharp. The thermodynamical variables show large discontinuities which is an indication for a first order phase transition. We solve the B=1 solitonic sector of the NJL model in the presence of an external hot quark and nucleon medium. In the hot medium at intermediate temperature the soliton is more bound and less swelled than in the case of a cold matter. At some critical temperature, which for the nucleon matter coincides with the critical temperature for the chiral phase transition, we find no more a localized solution. According to this model scenario one should expect a sharp phase transition from the nucleon to the quark matter.

LaTeX, using RevTeX and PiCTeX, 19 pages. Full postscript version also available on request or via ftp://hadron.tp2.ruhr-uni-bochum.de/preprint.tp2/1996/10-96.tar.gz

References in corpus (4)

• QCD Phenomenology based on a Chiral Effective Lagrangian
• The Phase Transition to the Quark Gluon Plasma: Recent Results from Lattice Calculations
• Hadronization cross--sections at the chiral phase transition of a quark plasma
• B=1 Soliton of the Nambu - Jona-Lasinio model in medium}

Cited by in corpus (9)

• Chiral soliton model at finite temperature and density
• Nontopological Soliton in the Polyakov Quark Meson Model
• Nucleon Properties in the Polyakov Quark Meson Model
• Molecular dynamics simulation for baryon-quark phase transition at finite temperature and density
• Baryonic matter and the medium modification of the baryon masses
• Nucleon Properties in the Quantized Linear Sigma Model at Finite Temperature and Chemical Potential
• The baryon mass calculation in the chiral soliton model at finite temperature and density
• Mean-field approximation for the chiral soliton in a chiral phase transition
• Linear Sigma Model at Finite Temperature and Baryonic Chemical Potential Using the Midpoint Technique