Neutrinos are known to play important roles in many astrophysical scenarios
from the early period of the big bang to current stellar evolution being a
unique messenger of the fusion reactions occurring in the center of our sun. In
particular, neutrinos are crucial in determining the dynamics and the
composition evolution in explosive events such as core-collapse supernovae and
the merger of two neutron stars. In this paper, we review the current
understanding of supernovae and binary neutron star mergers by focusing on the
role of neutrinos therein. Several recent improvements on the theoretical
modeling of neutrino interaction rates in nuclear matter as well as their
impact on the heavy element nucleosynthesis in the supernova neutrino-driven
wind are discussed, including the neutrino-nucleon opacity at the mean field
level taking into account the relativistic kinematics of nucleons, the effect
due to the nucleon-nucleon correlation, and the nucleon-nucleon bremsstrahlung.
We also review the framework used to compute the neutrino-nucleus interactions
and the up-to-date yield prediction for isotopes from neutrino nucleosynthesis
occurring in the outer envelope of the supernova progenitor star during the
explosion. Here improved predictions of energy spectra of supernova neutrinos
of all flavors have had significant impact on the nucleosynthesis yields. Rapid
progresses in modeling the flavor oscillations of neutrinos in these
environments, including several novel mechanisms for collective neutrino
oscillations and their potential impacts on various nucleosynthesis processes
are summarized.Comment: Review paper submitted to PPN