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arXiv · 1410.5981

Chiral dynamics in the low-temperature phase of QCD

Bastian B. Brandt·Anthony Francis·Harvey B. Meyer·Daniel Robaina
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Abstract

We investigate the low-temperature phase of QCD and the crossover region with two light flavors of quarks. The chiral expansion around the point $(T, m_q = 0)$ in the temperature vs. quark-mass plane indicates that a sharp real-time excitation exists with the quantum numbers of the pion. We determine its dispersion relation and test the applicability of the chiral expansion. The time-dependent correlators are also analyzed using the Maximum Entropy Method (MEM), yielding consistent results. Finally, we test the predictions of ordinary chiral perturbation theory around the point $(T = 0, m_q = 0)$ for the temperature dependence of static observables. Around the crossover temperature, we find that all quantities considered depend only mildly on the quark mass in the considered range 8MeV $\leq \bar{m}^{\bar{\text{MS}}} \leq$ 15MeV.

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Bastian B. Brandt, Anthony Francis, Harvey B. Meyer, Daniel Robaina. 2014-10-22. Chiral dynamics in the low-temperature phase of QCD. https://arxiv.org/abs/1410.5981

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