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arXiv · 1510.09196

Nonequilibrium meson production in strong fields

L. Juchnowski·D. Blaschke·T. Fischer·S. A. Smolyansky
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Abstract

We develop a kinetic equation approach to nonequilibrium pion and sigma meson production in a time-dependent, chiral symmetry breaking field (inertial mechanism). We investigate the question to what extent the low-momentum pion enhancement observed in heavy-ion collisions at CERN - LHC can be addressed within this formalism. In a first step, we consider the inertial mechanism for nonequilibrium production of $\sigma-$mesons and their simultaneous decay into pion pairs for two cases of $\sigma$ mass evolution. The resulting pion distribution shows a strong low-momentum enhancement which can be approximated by a thermal Bose distribution with a chemical potential that appears as a trace of the nonequilibrium process of its production.

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L. Juchnowski, D. Blaschke, T. Fischer, S. A. Smolyansky. 2015-10-30. Nonequilibrium meson production in strong fields. https://doi.org/10.1088/1742-6596%2F673%2F1%2F012009

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