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arXiv · 2211.15558

Aspects of chiral symmetry in QCD at T = 128 MeV

Marco Cè·Tim Harris·Ardit Krasniqi·Harvey B. Meyer·Csaba Török
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Abstract

We investigate several aspects of chiral symmetry in QCD at a temperature of $T = 128\,\text{MeV}$. The study is based on a $24\times 96^3$ lattice-QCD ensemble with O($a$)-improved Wilson quarks and physical up, down and strange quark masses. The pion quasiparticle turns out to be significantly lighter than the zero-temperature pion mass, even though the corresponding static correlation length is shorter. We perform a quantitative comparison of our findings to predictions of chiral perturbation theory. Among several order parameters for chiral symmetry restoration, we compute the difference of the vector- and axial-vector time-dependent correlators and find it to be reduced by a factor $\sim2/3$ as compared to its vacuum counterpart.

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Marco Cè, Tim Harris, Ardit Krasniqi, Harvey B. Meyer, Csaba Török. 2022-11-28. Aspects of chiral symmetry in QCD at T = 128 MeV. https://doi.org/10.1103/physrevd.107.054509

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