# Scotogenic $U(1)_\chi$ Dirac Neutrinos

## TL;DR

This paper explores models extending the Standard Model with a $U(1)_ ext{chi}$ gauge symmetry, generating Dirac neutrino masses radiatively via dark matter, and presents two examples with different dark matter candidates and properties.

## Contribution

It introduces two novel models for Dirac neutrino mass generation involving dark matter within a $U(1)_ ext{chi}$ framework, highlighting their distinct dark matter candidates and decay mechanisms.

## Key findings

- One model supports light Dirac fermion dark matter.
- The other features self-interacting scalar dark matter with a neutrino-decaying scalar mediator.

## Abstract

The standard model of quarks and leptons is extended to include the gauge symmetry $U(1)_\chi$ which comes from $SO(10) \to SU(5) \times U(1)_\chi$. The radiative generation of Dirac neutrino masses through dark matter is discussed in two examples. One allows for light Dirac fermion dark matter. The other allows for self-interacting scalar dark matter with a light scalar mediator which decays only to two neutrinos.