Neutrino-nucleon scattering rate in the relativistic random phase approximation

por Lysiane Mornas (Universidad de Oviedo)

jueves 4 oct. 2001 12:30 → 13:30 Europe/Madrid

Sala Seminarios (Dpto. de Física Teórica (UVEG))

We calculate the in-medium modification to neutrino-nucleon scattering in the relativistic random phase approximation in the framework of a relativistic hadronic field theory with sigma, omega, pi, rho and delta mesons exchange. In view of applications to neutrino transport in protoneutron stars, we study the evolution of the neutrino opacity as a function of density, asymmetry and temperature Special attention was paid to the issues of renormalization of vacuum fluctuations, short range residual interaction and meson mixing. In contrast to previous work where strong reduction factors were predicted, RPA corrections with respect to the mean field approximation amounting to only 10% to 15% at high density were found in this work. When meson mixing is fully taken into account, the reduction factor is found to be even smaller.