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arXiv · 1104.2819

Thermodynamics of the in-medium chiral condensate

S. Fiorilla·N. Kaiser·W. Weise
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Abstract

The temperature dependence of the chiral condensate in isospin-symmetric nuclear matter at varying baryon densities is investigated starting from a realistic free energy density of the correlated nuclear many-body system. The framework is thermal in-medium chiral effective field theory which permits a systematic calculation of the quark mass dependence of the free energy density. One- and two-pion exchange processes, virtual $\Delta(1232)$-isobar excitations and Pauli blocking corrections are treated up to and including three-loop order. It is found that nuclear matter remains in the Nambu-Goldstone phase with spontaneously broken chiral symmetry at least in the range of temperatures $T\lesssim 100\,$MeV and baryon densities up to about twice the density of normal nuclear matter.

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S. Fiorilla, N. Kaiser, W. Weise. 2011-04-14. Thermodynamics of the in-medium chiral condensate. https://arxiv.org/abs/1104.2819

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