Sterile neutrinos in U(1)' with R-parity Violation

TL;DR

This paper explores how U(1)' supersymmetric models with R-parity violation can naturally produce sterile neutrinos that explain certain neutrino oscillation anomalies, with specific predictions for their masses and mixings.

Contribution

It introduces a framework where R-parity breaking induces neutralino-neutrino mixing, leading to light sterile neutrinos with constrained properties in U(1)' models.

Findings

Sterile neutrinos can be light and act as dark matter candidates.

Mass and mixing parameters are highly restricted by neutrino data.

Predictive features emerge for sterile neutrinos in U(1)' scenarios.

Abstract

Motivated by results from short-baseline neutrino oscillation data, we study neutrino masses and mixing in U(1)' supersymmetric models with R-parity breaking. Whether R-parity is broken spontaneous or through (effective) bilinear terms in the Lagrangian, the breaking terms induce mixing between the neutralinos and neutrinos, creating a scenario in which some neutralinos can be heavy, and some light. Both the right-handed neutrino and the singlino (fermionic partner of the additional singlet Higgs field) can be light, and act as sterile neutrinos, which reconcile some of the anomalies observed in solar baseline and reactor experiments. We show that, scanning a large range of the parameter space satisfying solar and atmospheric neutrino constraints, the mass and mixing parameters of the sterile neutrinos are very restrictive, leading to some predictive features for the U(1)' scenarios.