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Temperature Dependence of the Chiral Condensate from an Interacting Pion Gas

G. Bunatian·J. Wambach
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Abstract

By exploiting the fact that the chiral condensate is related to the derivative of the free-energy density with respect to the bare quark mass we calculate the temperature dependence of the condensate ratio $\ave{\bar qq}_T/\ave{\bar qq}_0$ from an iteracting pion gas. When using the Weinberg Lagrangian at the Hartree level we find a depression of the condensate with temperature. For $T < 100$ MeV the results are in good agreement with chiral perturbation theory in the three loop approximation. Near $T_c$, however, there are marked differences due to non-perturbative nature of our approach.

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G. Bunatian, J. Wambach. 1994-06-16. Temperature Dependence of the Chiral Condensate from an Interacting Pion Gas. https://doi.org/10.1016/0370-2693(94)90534-7

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