The nature of the Roberge-Weiss Transition in $N_f=2$ QCD with Wilson Fermions on $N_\tau=6$ lattices

TL;DR

This study investigates the nature and location of tricritical points in the Roberge-Weiss transition for $N_f=2$ Wilson fermions at finite temperature on $N_ au=6$ lattices, extending previous $N_ au=4$ results.

Contribution

It provides new insights into how the tricritical points shift with increased lattice temporal extent, using finite size scaling analysis for $N_f=2$ Wilson fermions.

Findings

Tricritical points' locations change with $N_ au$ increase.

Finite size scaling confirms the nature of the transition points.

Comparison with previous $N_ au=4$ results highlights lattice spacing effects.

Abstract

The finite temperature chiral and deconfinement phase transitions at zero density for light and heavy quarks, respectively, have analytic continuations to imaginary chemical potential. At some critical imaginary chemical potential, they meet the Roberge-Weiss transition between adjacent $Z(3)$ sectors. For light and heavy quarks, where the chiral and deconfinement transitions are first order, the transition lines meet in a triple point. For intermediate masses chiral or deconfinement transitions are crossover and the Roberge-Weiss transition ends in a second order point. At the boundary between these regimes the junction is a tricritical point, as shown in studies with $N_f=2,3$ flavors of staggered and Wilson quarks on $N_\tau=4$ lattices. Employing finite size scaling we investigate the nature of this point as a function of quark mass for $N_f=2$ flavors of Wilson fermions with a temporal lattice extent of $N_\tau=6$. In particular we are interested in the change of the location of tricritical points compared to our ealier study on $N_\tau=4$.