Determination of the endpoint of the first order deconfiniement phase transition in the heavy quark region of QCD

TL;DR

This paper investigates the critical endpoint of the first order deconfinement phase transition in heavy quark QCD using reweighting, hopping parameter expansion, and finite-size scaling to understand phase transition behavior.

Contribution

The study introduces a method combining reweighting with hopping parameter expansion and external sources to locate the critical point in heavy quark QCD.

Findings

Identified the critical point where the phase transition changes from first order to crossover.

Analyzed the effects of lattice spacing and volume on the critical point estimation.

Estimated the truncation error of the hopping parameter expansion.

Abstract

We study the endpoint of the first order deconfinement phase transition of 2 and 2+1 flavor QCD in the heavy quark region. We perform simulations of quenched QCD and apply the reweighting method to study the heavy quark region. The quark determinant for the reweighting is evaluated by a hopping parameter expansion. To reduce the overlap problem, we introduce an external source term of the Polyakov loop in the simulation. We study the location of critical point at which the first order phase transition changes to crossover by investigating the histogram of the Polyakov loop and applying the finite-size scaling analysis. We estimate the truncation error of the hopping parameter expansion, and discuss the lattice spacing dependence and the spatial volume dependence in the result of the critical point.