Current quark mass effects on the chiral phase transition of QCD in the improved ladder approximation

O. Kiriyama, M. Maruyama, F. Takagi

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Current quark mass effects on the chiral phase transition of QCD are studied in the improved ladder approximation. The infrared behavior of the gluon propagator is modified in terms of an effective running coupling. The analysis is based on a composite operator formalism and a variational approach. We use the Schwinger-Dyson equation to give a "normalization condition" for the Cornwall-Jackiw-Tomboulis effective potential and to isolate the ultraviolet divergence that appears in the expression for the quark-antiquark condensate. We study the current quark mass effects on the order parameter at zero temperature and density. We then calculate the effective potential at finite, temperature and density and investigate the current quark mass effects on the chiral phase transition. We find a smooth crossover for T>0, μ=0 and a first-order phase transition for μ>0, T=0. Critical exponents are also studied and our model gives the classical mean-field values. We also study the temperature dependence of the masses of scalar and pseudoscalar bosons. A critical end point in the T-μ plane is found at T∼100 MeV, μ∼300 MeV.

Original languageEnglish
Article number116009
Pages (from-to)1160091-11600911
Number of pages10440821
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume63
Issue number11
Publication statusPublished - 2001 Aug 15
Externally publishedYes

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Fingerprint Dive into the research topics of 'Current quark mass effects on the chiral phase transition of QCD in the improved ladder approximation'. Together they form a unique fingerprint.

  • Cite this