Pion properties at finite density

TL;DR

This paper investigates how the pion decay constant and mass change at finite density using a nonlocal chiral quark model, revealing a slight decrease in decay constants and a 15% increase in pion mass near the critical chemical potential.

Contribution

It provides a detailed calculation of pion properties at finite density considering Lorentz invariance breaking, which is a novel aspect in this context.

Findings

F^t_pi = 82.96 MeV at mu_c

F^s_pi = 80.29 MeV at mu_c

Pion mass increases by about 15% at mu_c

Abstract

In this talk, we report our recent work on the pion weak decay constant (F_pi) and pion mass (m_pi) using the nonlocal chiral quark model with the finite quark-number chemical potential (mu) taken into account. Considering the breakdown of Lorentz invariance at finite density, the time and space components are computed separately, and the corresponding results turn out to be: F^t_pi = 82.96 MeV and F^s_pi = 80.29 MeV at mu_c ~ 320 MeV, respectively. Using the in-medium Gell-Mann Oakes-Renner (GOR) relation, we show that the pion mass increases by about 15% at mu_c.