Current quark mass and chiral-symmetry breaking in QCD at finite temperature in a mean-field approximation

Journal Article · Tue Sep 01 00:00:00 EDT 1992 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.46.2203· OSTI ID:7258803

Barducci, A; Casalbuoni, R ^[1]; De Curtis, S ^[2]; Gatto, R ^[3]; Pettini, G ^[1]

---

1. Dipartimento di Fisica, Universita di Firenze, I-50125 Firenze (Italy) Istituto Nazionale di Fisica Nucleare, Sezione di Firenze, I-50125 Firenze (Italy)
2. Istituto Nazionale di Fisica Nucleare, Sezione di Firenze, I-50125 Firenze (Italy)
3. Departement de Physique Theorique, Universite de Geneve, CH-1211 Geneve 4 (Switzerland)

The effects of current quark masses on chiral-symmetry breaking in QCD at finite temperature are examined using a mean-field approximation. The current quark mass plays a role analogous to that of an external magnetic field in the ferromagnetic transition, as it explicitly violates the chiral symmetry whose restoration characterizes the phase transition. For small enough masses, the order parameter, related to the quark condensate, maintains the features of the massless case up to the critical temperature, and then it approaches a constant value depending on the current mass term itself. The consequences on the behavior of the pion mass and decay constant are also studied. Our calculations are done with a variational composite operator approach. We also discuss the critical exponents (in temperature, mass, and for susceptibility) that follow in general from assuming the possible validity of a Landau mean-field theory.

• OSTI ID: 7258803
• Journal Information: Physical Review, D (Particles Fields); (United States), Vol. 46:5; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
QUANTUM CHROMODYNAMICS
CHIRAL SYMMETRY
QUARKS
MASS
DECAY
FERROMAGNETISM
INFRARED DIVERGENCES
MAGNETIC FIELDS
MAGNETIZATION
MEAN-FIELD THEORY
PHASE TRANSFORMATIONS
PIONS
POTENTIALS
SYMMETRY BREAKING
TEMPERATURE DEPENDENCE
BOSONS
ELEMENTARY PARTICLES
FERMIONS
FIELD THEORIES
HADRONS
MAGNETISM
MESONS
POSTULATED PARTICLES
PSEUDOSCALAR MESONS
QUANTUM FIELD THEORY
SYMMETRY
662110* - General Theory of Particles & Fields- Theory of Fields & Strings- (1992-)
662120 - General Theory of Particles & Fields- Symmetry
Conservation Laws
Currents & Their Properties- (1992-)
662350 - Decays of Mesons- (1992-)