First-order phase transition in dynamical 3-flavor QCD at imaginary isospin

TL;DR

This study investigates the phase transition in three-flavor QCD at an imaginary isospin chemical potential, revealing a first-order transition with singular behavior at a specific symmetry point.

Contribution

It demonstrates, through finite-size scaling and simulations, that the finite temperature transition in this QCD setup is of first order, highlighting a special symmetry point.

Findings

First-order phase transition identified at the special symmetry point.

Singular behavior observed in Polyakov loop and quark condensate.

Finite-size scaling confirms the nature of the transition.

Abstract

We revisit QCD with three mass-degenerate quark flavors at an imaginary isospin chemical potential set to 4 pi T/3. This choice corresponds to a special point in the parameter space, where the theory possesses an exact Z(3) center symmetry. Through a finite-size scaling analysis, we demonstrate that in this case the finite temperature QCD transition is of first order and entails singular behavior both in the Polyakov loop and in the quark condensate. Our results are based on simulations with stout-smeared staggered quarks and a dedicated multi-histogram analysis.