MEDIUM-MODIFIED INTERACTION-INDUCED BY FLUCTUATIONS

Statistical averaging of the Boltzmann-Langevin equation is performed. It is shown that at the averaged level the fluctuations induce an additional collision term with a medium-modified transition rate, which can give rise to a critical scattering phenomena in the vicinity of unstable regions. In order to illustrate the effect of this additional collision term, the single-particle relaxation time in nuclear matter is estimated. It is shown that the fluctuation-induced contribution to the relaxation time is indeed comparable with that of the BUU collision term in the vicinity of spinoidal region.