The QCD deconfinement critical point for $N_\tau=8$ with $N_f=2$ flavours of unimproved Wilson fermions

TL;DR

This study investigates the QCD deconfinement critical point using Wilson fermions at finite lattice spacing, analyzing phase transition behavior and finite size effects to assess continuum limit extrapolation.

Contribution

It provides the first detailed analysis of the deconfinement critical point for Nf=2 Wilson fermions at N_tau=8, including finite size scaling and continuum extrapolation considerations.

Findings

Finite size scaling analysis performed on N_tau=8 lattices.

Assessment of continuum limit extrapolation feasibility.

Identification of the critical point behavior at finite lattice spacing.

Abstract

QCD at zero baryon density in the limit of infinite quark mass undergoes a first order deconfinement phase transition at a critical temperature $T_c$ corresponding to the breaking of the global centre symmetry. In the presence of dynamical quarks this symmetry is explicitly broken. Lowering the quark mass the first order phase transition weakens and terminates in a second order Z(2) point. Beyond this line confined and deconfined regions are analytically connected by a crossover transition. As the continuum limit is approached (i.e. the lattice spacing is decreased) the region of first order transitions expands towards lower masses. We study the deconfinement critical point with standard Wilson fermions and $N_f=2$ flavours. To this end we simulate several kappa values on $N_\tau=8$ and various aspect ratios in order to extrapolate to the thermodynamic limit, applying finite size scaling. We estimate if and when a continuuum extrapolation is possible.