Speaker
Description
We investigate meson properties in a three-flavor quark–meson (linear sigma) model at finite temperature and isospin chemical potential. The model incorporates explicit chiral symmetry breaking as well as the $U _A(1)$ anomaly via the Kobayashi–Maskawa–’t Hooft (KMT) interaction. Working in the mean-field approximation, we introduce both chiral condensates and a pion condensate to describe the possible emergence of a pion superfluid phase at large isospin density.
At tree level, we derive the meson mass spectra and analyze the mixing patterns among scalar and pseudoscalar modes, emphasizing the role of the anomaly term in splitting the flavor-singlet and octet channels. We then extend the analysis to one-loop order using the Matsubara formalism. The thermodynamic potential is constructed by including quark fluctuations, and the gap equations for the condensates are solved self-consistently.
We compute meson propagators and extract the in-medium spectra from the pole conditions, both in the normal phase and in the pion superfluid phase where meson mixing becomes nontrivial. The interplay between isospin density, chiral symmetry breaking, and the $U_A(1)$ anomaly is systematically explored. In particular, we discuss how the pion condensation modifies the meson spectrum and induces mixing between scalar and pseudoscalar channels.
Our results provide a unified framework to study meson properties at finite isospin density and may offer insights relevant to QCD phase structure and strongly interacting matter under extreme conditions.