Non-standard neutrino interactions and neutral gauge bosons

Abstract

We investigate Non-Standard Neutrino Interactions (NSI) arising from a flavor-sensitive Z0 boson of a new U(1)0 symmetry. We compare the limits from neutrino oscillations, coherent elastic neutrino–nucleus scattering, and Z0 searches at different beam and collider experiments for a variety of straightforward anomaly-free U(1)0 models generated by linear combinations of B − L and lepton-family-number differences Lα − Lβ. Depending on the flavor structure of those models it is easily possible to avoid NSI signals in long-baseline neutrino oscillation experiments or change the relative importance of the various experimental searches. We also point out that kinetic Z–Z0 mixing gives vanishing NSI in long-baseline experiments if a direct coupling between the U(1)0 gauge boson and matter is absent. In contrast, Z–Z0 mass mixing generates such NSI, which in turn means that there is a Higgs multiplet charged under both the Standard Model and the new U(1)0 symmetry.