8 Theoretical update on low energy neutrino – nucleus reactions

We review Quasielastic (QE) inclusive and semi–inclusive neutrino/antineutrino Charged Current (CC) and Neutral Current (NC) induced nuclear reactions at intermediate energies. We pay special attention to nuclear corrections besides Pauli blocking: Long and Short range nuclear correlations (RPA and SRC) and particle and hole Spectral Functions (SF). We also critically review the use of the Plane and Distorted Wave Impulse approximations (PWIA and DWIA) to describe inclusive one nucleon knockout reactions off nuclei. In this context, we present results from a Monte Carlo cascade method to account for the rescattering of the outgoing nucleon. Finally, we examine the effects of chiral non-resonant terms in neutrino pion production off the nucleon, and present some preliminary results on nuclear coherent pion production induced by neutrinos.