Ultraviolet extensions of the Scotogenic model

TL;DR

This paper classifies all ultraviolet extensions of the Scotogenic model where dark matter stability and neutrino masses arise from spontaneously broken lepton number symmetry, exploring their phenomenological implications.

Contribution

It systematically identifies 50 models with low-energy dark matter stability emerging from high-energy lepton number breaking, and analyzes their phenomenology.

Findings

50 models classified with spontaneous lepton number breaking

Detailed discussion of two representative models

Rich phenomenology including lepton flavor violation and collider signals

Abstract

The Scotogenic model is a popular scenario that induces radiative Majorana neutrino masses and includes a weakly-interacting dark matter candidate. We classify all possible ultraviolet extensions of the Scotogenic model in which (i) the dark $\mathbb{Z}_2$ parity emerges at low energies after the spontaneous breaking of a global $\rm U(1)_L$ lepton number symmetry, and (ii) the low-energy effective theory contains a naturally small lepton number breaking parameter, suppressed by the mass of a heavy mediator integrated out at tree-level. We find $50$ such models and discuss two of them in detail to illustrate our setup. We also discuss some general aspects of the phenomenology of the models in our classification, exploring possible lepton flavor violating signals, collider signatures and implications for dark matter. The phenomenological prospects of these scenarios are very rich due to the presence of additional scalar states, including a massless Goldstone boson.