2009/07/31 by Kohtaroh Miura, T. Nakano, Takashi Z. Nakano +2
Physics and Astronomy · #High-Energy Particle Collisions Research #Physics of Superconductivity and Magnetism #Quantum Chromodynamics and Particle Interactions #hep-lat #nucl-th
paper · pdf · doi:10.1103/physrevd.80.074034
published as Phys.Rev.D80:074034,2009 · 17 pages, 9 figures
arxiv created 2009/10/06 · openalex publication_date 2009/10/28 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We investigate the chiral phase transition in the strong coupling lattice QCD at finite temperature and density with finite coupling effects. We adopt one species of staggered fermion, and develop an analytic formulation based on strong coupling and cluster expansions. We derive the effective potential as a function of two order parameters, the chiral condensate \ensuremathσ and the quark number density \ensuremathρq, in a self-consistent treatment of the next-to-leading order (NLO) effective action terms. NLO contributions lead to modifications of quark mass, chemical potential, and the quark wave function renormalization factor. While the ratio \ensuremathμc(T=0)/Tc(\ensuremathμ=0) is too small in the strong coupling limit, it is found to increase as \ensuremathβ=2Nc/g2 increases. The critical point is found to move in the lower T direction as \ensuremathβ increases. Since the vector interaction induced by \ensuremathρq is shown to grow as \ensuremathβ, the present trend is consistent with the results in Nambu-Jona-Lasinio models. The interplay between two order parameters leads to the existence of partially chiral restored matter, where effective chemical potential is automatically adjusted to the quark excitation energy.