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arXiv · 2212.14461

Progress on the QCD deconfinement critical point for $N_\text{f}=2$ staggered fermions

Reinhold Kaiser·Owe Philipsen
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Abstract

The global center symmetry of quenched QCD at zero baryonic chemical potential is broken spontaneously at a critical temperature $T_c$ leading to a first-order phase transition. Including heavy dynamical quarks breaks the center symmetry explicitly and weakens the first-order phase transition for decreasing quark masses until it turns into a smooth crossover at a $Z(2)$-critical point. We investigate the $Z(2)$-critical quark mass value towards the continuum limit for $N_\text{f}=2$ flavors using lattice QCD in the staggered formulation. As part of a continued study, we present results from Monte-Carlo simulations on $N_\tau=8,10$ lattices. Several aspect ratios and quark mass values were simulated in order to obtain the critical mass from a fit of the Polyakov loop to a kurtosis finite size scaling formula. Moreover, the possibility to develop a Ginzburg-Landau effective theory around the $Z(2)$-critical point is explored.

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Reinhold Kaiser, Owe Philipsen. 2022-12-29. Progress on the QCD deconfinement critical point for $N_\text{f}=2$ staggered fermions. https://arxiv.org/abs/2212.14461

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