Universal scaling properties of QCD close to the chiral limit
Abstract
We present a lattice QCD based determination of the chiral phase transition temperature in QCD with two massless (up and down) and one strange quark having its physical mass. We propose and calculate two novel estimators for the chiral transition temperature for several values of the light quark masses, corresponding to Goldstone pion masses in the range of $58~{\rm MeV}\lesssim m_\pi\lesssim 163~{\rm MeV}$. The chiral phase transition temperature is determined by extrapolating to vanishing pion mass using universal scaling relations. After thermodynamic, continuum and chiral extrapolations we find the chiral phase transition temperature $T_c^0=132^{+3}_{6}$ MeV. We also show some preliminary calculations that use the conventional estimator for the pseudocritical temperature and compare with the new estimators for $T_c^0$. Furthermore, we show results for the ratio of the chiral order parameter and its susceptibility and argue that this ratio can be used to differentiate between $O(N)$ and $Z_2$ universality classes in a nonparametric manner.
 Publication:

arXiv eprints
 Pub Date:
 October 2020
 DOI:
 10.48550/arXiv.2010.15593
 arXiv:
 arXiv:2010.15593
 Bibcode:
 2020arXiv201015593K
 Keywords:

 High Energy Physics  Lattice;
 High Energy Physics  Phenomenology;
 Nuclear Theory
 EPrint:
 10 pages, 6 figures, contribution to the proceeding of workshop on Criticality in QCD and the Hadron Resonance Gas