Neutrino propagation and spin zero sound in hot neutron matter with Skyrme-interactions - art. no. 045801

We present microscopic calculations of neutrino propagation in hot neutron matter above the nuclear density within the framework of the random phase a pproximation. Calculations are performed for nondegenerate neutrinos using various Skyrme effective interactions. We find that for densities just abov e the nuclear density, spin zero sound is present at zero temperature for a ll Skyrme forces considered. However, it disappears rapidly with increasing temperature due to a strong Landau damping. As a result the mean free path is given, to a good approximation, by the mean field value. Because of the renormalization of the bare mass in the mean field, the medium is more tra nsparent as compared to the free case. We find, in contrast, that at severa l times the nuclear density, a new type of behavior sets in due to the vici nity of a magnetic instability. It produces a strong reduction of the mean free path. The corresponding transition density, however, occurs ina region where inputs from more realistic calculations are necessary for the constr uction of a reliable Skyrme-type parametrization. [S0556-2813(99)00910-3].