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arXiv · 2209.05887

Kinetics of the chiral phase transition in a quark-meson $σ$ model

H. van Hees·A. Meistrenko·C. Greiner
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Abstract

Using the two-particle irreducible (2PI) $Φ$-functional formalism for self-consistent approximations of a linear-$σ$ model for quarks and mesons in and out of equilibrium, the build-up of fluctuations of net-baryon number during the time evolution of an expanding fireball is studied within a kinetic theory for the order parameter ($σ$ field) and quark distribution functions. Initializing the system with purely Gaussian fluctuations a fourth-order cumulant is temporarily built up due to the evolution of the $σ$-field. This is counterbalanced, however, by the dissipative evolution due to collisions between quarks, anti-quarks, mesons, and the mean field, depending on the speed of the fireball expansion.

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H. van Hees, A. Meistrenko, C. Greiner. 2022-09-13. Kinetics of the chiral phase transition in a quark-meson $σ$ model. https://doi.org/10.5506/aphyspolbsupp.16.1-a89

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