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Thermal and Nonthermal Pion Enhancements with Chiral Symmetry Restoration

P. Zhuang·Z. Yang
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Abstract

The pion production by sigma decay and its relation with chiral symmetry restoration in a hot and dense matter are investigated in the framework of the Nambu-Jona-Lasinio model. The decay rate for the process sigma -> 2pion to the lowest order in a 1/N_c expansion is calculated as a function of temperature T and chemical potential mu. The thermal and nonthermal enhancements of pions generated by the decay before and after the freeze-out present only in the crossover region of the chiral symmetry transition. The strongest nonthermal enhancement is located in the vicinity of the endpoint of the first-order transition.

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P. Zhuang, Z. Yang. 2000-09-21. Thermal and Nonthermal Pion Enhancements with Chiral Symmetry Restoration. https://doi.org/10.1103/physrevd.63.016004

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