A Natural Scotogenic Model for Neutrino Mass \& Dark Matter

TL;DR

This paper introduces an extended scotogenic model that naturally generates neutrino masses and dark matter candidates without requiring extremely suppressed couplings, offering richer phenomenology and broader viable mass ranges.

Contribution

It proposes a novel extension of the scotogenic model with a specific symmetry breaking pattern, enabling neutrino mass generation and dark matter stability without tiny couplings.

Findings

Neutrino masses achieved via diagram cancellations.

Dark matter candidate viable over a large mass range.

Enhanced phenomenology compared to minimal models.

Abstract

In this letter, we propose an extension of the scotogenic model where singlet Majorana particle can be dark matter (DM) without the need of a highly suppressed scalar coupling of the order $O(10^{-10})$. For that, the SM is extended with three singlet Majorana fermions, an inert scalar doublet, and two (a complex and a real) singlet scalars, with a global $Z_{4}$ symmetry that is spontaneously broken into $Z_{2}$ at a scale higher than the electroweak one by the vev of the complex singlet scalar. In this setup, the smallness of neutrino mass is achieved via the cancellation between three diagrams a la scotogenic, a DM candidate that is viable for a large mass range; and the phenomenology is richer than the minimal scotogenic model.