Vector and axialvector mesons at nonzero temperature within a gauged linear sigma model

TL;DR

This paper studies how vector and axialvector mesons behave at nonzero temperature using a gauged linear sigma model, revealing that their inclusion sharpens the chiral transition and affects meson masses.

Contribution

It introduces a detailed analysis of vector and axialvector mesons at finite temperature within a gauged linear sigma model using Dyson-Schwinger equations.

Findings

Chiral transition becomes sharper with vector and axialvector mesons.

The rho meson mass increases by about 100 MeV near the transition.

The model provides insights into meson mass behavior at high temperatures.

Abstract

We consider vector and axialvector mesons in the framework of a gauged linear sigma model with chiral $U(N_f)_R \times U(N_f)_L$ symmetry. For $N_f=2$, we investigate the behavior of the chiral condensate and the meson masses as a function of temperature by solving a system of coupled Dyson-Schwinger equations derived via the 2PI formalism in double-bubble approximation. We find that the inclusion of vector and axialvector mesons tends to sharpen the chiral transition. Within our approximation scheme, the mass of the $\rho$ meson increases by about 100 MeV towards the chiral transition.