Microdynamical effects on momentum distribution in stellar plasmas

Abstract

We show that, if a random force is present, the microscopic dynamics of ion elastic collisions and quantum effects may sensibly modify the momentum distribution of ions and electrons in stellar plasmas. We also show that a few microscopic interactions among the particles, that are significant in very specific energy intervals, lead to peculiar slight corrections to the usual MaxwellBoltzmann distribution. All these modifications can be easily taken into account by using the nonextensive statistical mechanics. Consequences on the resonant and non-resonant fusion rates are remarkable and may affect strongly some astrophysical processes. A few examples are reported.