Chiral Symmetry and hadron properties at finite temperature -A numerical experiment

TL;DR

This study investigates how hadron properties change at finite temperature using lattice QCD simulations, observing degeneracy in screening masses indicating symmetry restoration and approaching free quark behavior.

Contribution

It provides numerical evidence of chiral and U_A(1) symmetry restoration in two-flavor QCD at finite temperature through screening mass measurements.

Findings

Screening masses in all channels tend to degenerate at high temperature.

Screening masses approach the free quark limit of 2πT.

Below T_c, screening masses decrease in all channels.

Abstract

We study the hadron properties at finite temperature from measurement of the screening masses, using two-flavor full QCD of the hybrid Monte Carlo (HMC) algorithm with the renormalization group improved Iwasaki gauge action and the clover improved Wilson quark action on a $16^3 \times 4$ lattice. We explore rather heavy quark mass regions. Disconnected quark diagram is dropped. We observe the tendency that the screening masses in all the channels degenerate, which is in accord with the effective restoration of U$_{\rm A}$(1) symmetry, and then eventually approach 2$\pi T$, i.e. the free quark value. In the low temperature region below pseudocritical temperature $T_c$, the screening masses in all the channels decrease. We discuss the different features between these calculations and the previous ones.