Aspects of Meson Condensation

TL;DR

This paper investigates pion and kaon condensation using chiral perturbation theory at zero temperature, analyzing meson masses, mixing, and decay channels across different phases with nonzero isospin and strangeness chemical potentials.

Contribution

It provides a detailed analysis of meson condensation phases, highlighting differences from previous studies and supporting results with theoretical and direct calculations.

Findings

Meson masses and mixing vary across phases.

Decay width of pion decay channels shows nonmonotonic behavior.

Results differ from prior works but are well-supported.

Abstract

In this work pion and kaon condensation in the framework of chiral perturbation theory is studied. I consider a system at vanishing temperature with nonzero isospin chemical potential and strangeness chemical potential; meson masses and mixing in the normal phase, the pion condensation phase and the kaon condensation phase are described. There are differences with previous works, but the results presented here are supported by both theory group analysis and by direct calculations. Some pion decay channels in the normal and the pion condensation phases are studied, finding a nonmonotonic behavior of the $\Gamma$ decay width as a function of $\mu_I$.