Neutrino Mass and Dark Matter from Gauged $U(1)_{B-L}$ Breaking

TL;DR

This paper introduces a model where neutrino masses and dark matter originate from the spontaneous breaking of a gauged $U(1)_{B-L}$ symmetry, linking neutrino mass generation with dark matter stability and phenomenology.

Contribution

The model uniquely combines neutrino mass generation and dark matter stability via anomaly-free $U(1)_{B-L}$ breaking, with dark matter stabilizing through an associated global symmetry.

Findings

Model satisfies neutrino oscillation constraints

Dark matter relic abundance matches observations

Predicts signals testable at future colliders and dark matter experiments

Abstract

We propose a new model where the Dirac mass term for neutrinos, the Majorana mass term for right-handed neutrinos, and the other new fermion masses arise via the spontaneous breakdown of the $U(1)_{B-L}$ gauge symmetry. The anomaly-free condition gives four sets of assignment of the B-L charge to new particles, and three of these sets have an associated global $U(1)_{DM}$ symmetry which stabilizes dark matter candidates. The dark matter candidates contribute to generating the Dirac mass term for neutrinos at the one-loop level. Consequently, tiny neutrino masses are generated at the two-loop level via a Type-I-Seesaw-like mechanism. We show that this model can satisfy current bounds from neutrino oscillation data, the lepton flavor violation, the relic abundance of the dark matter, and the direct search for the dark matter. This model would be tested at future collider experiments and dark matter experiments.