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arXiv · 2004.07122

Finite temperature QCD with $N_f=2+1+1$ Wilson twisted mass fermions at physical pion, strange and charm masses

Andrey Yu. Kotov·Maria Paola Lombardo·Anton M. Trunin
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Abstract

We discuss recent progress in studying Quantum Chromodynamics at finite temperature using $N_f=2+1+1$ Wilson twisted mass fermions. Particular interest is in QCD symmetries and their breaking and restoration. First, we discuss the behaviour of the $\eta'$ meson at finite temperature, which is tightly connected to the axial and chiral symmetries. The results suggest a small decrease of the $\eta'$ mass in the pseudo-critical region coming close to the non-anomalous contribution and subsequent growth at large temperatures. Second, we present the first results of lattice simulations of Quantum Chromodynamics with $N_f=2+1+1$ twisted mass Wilson fermions at physical pion, strange and charm masses. We estimate the chiral pseudo-critical temperatures for different observables. Our preliminary results are consistent with a second order transition in the chiral limit, however other scenarios are not excluded.

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Andrey Yu. Kotov, Maria Paola Lombardo, Anton M. Trunin. 2020-04-15. Finite temperature QCD with $N_f=2+1+1$ Wilson twisted mass fermions at physical pion, strange and charm masses. https://doi.org/10.1140/epja/s10050-020-00216-7

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