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Dynamical Evolution of the Scalar Condensate in Heavy Ion Collisions

Laszlo P. Csernai·Paul J. Ellis·Sangyong Jeon·Joseph I. Kapusta
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Abstract

We derive the effective coarse-grained field equation for the scalar condensate of the linear sigma model in a simple and straightforward manner using linear response theory. The dissipative coefficient is calculated at tree level on the basis of the physical processes of sigma-meson decay and of thermal sigma-mesons and pions knocking sigma-mesons out of the condensate. The field equation is solved for hot matter undergoing either one or three dimensional expansion and cooling in the aftermath of a high energy nuclear collision. The results show that the time constant for returning the scalar condensate to thermal equilibrium is of order 2 fm/c.

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Laszlo P. Csernai, Paul J. Ellis, Sangyong Jeon, Joseph I. Kapusta. 2000-02-22. Dynamical Evolution of the Scalar Condensate in Heavy Ion Collisions. https://doi.org/10.1103/physrevc.61.054901

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