Profiles of the broken string in two-flavor QCD below and above the finite temperature transition

TL;DR

This study investigates how the flux tube profiles of mesonic and baryonic configurations in two-flavor QCD change across the finite-temperature transition, revealing string breaking below T_c and flux disappearance above T_c.

Contribution

It provides the first detailed comparison of flux tube profiles in mesonic and baryonic systems across the QCD finite-temperature transition.

Findings

String breaking observed at large quark separation below T_c.

Electric field becomes Coulomb-like above T_c.

Flux tube disappears above the critical temperature T_c.

Abstract

We study the Abelian flux tube profile of mesonic and the baryonic configurations of static quarks below and above the finite-temperature transition in $N_f=2$ full QCD. To reduce effects of ultra-violet fluctuations we measure Abelian distributions of the action density, the color-electric field and the monopole current after fixing to the maximally Abelian gauge. Changing the distance $R$ between quarks for fixed $T/T_c<1$, one can see a clear signal of string breaking for large $R$. The electric field becomes Coulomb-like and the circulating monopole current disappears. We study also the temperature dependence of the flux profile for fixed $R \approx 0.7$ fm. The disappearance of the squeezed flux is observed clearly above $T_c$. Similar behaviors are observed both in the mesonic and the baryonic systems.