Open Issues in Neutrino Reactions

Numerous investigations discuss neutrino properties from low to ultra high energies. This review discusses several topics that are investigated in present day experiments. The first section covers the detection of $\tau$-neutrinos of cosmic origin and describes the significance of the results. The second topic points out that the reported reduction of the antineutrino flux in reactor experiments may be created by short wavelength oscillations where the detector averages over several wavelengths and observes only an average reduction of the antineutrino flux. In many theories the propagating particles are Majoranas and have an anapole moment; they scatter on atomic electrons with a distinct signature in $\bar\nu_e+e^-\rightarrow\bar\nu_e+e^-$ scattering.