What a direct neutrino mass measurement might teach us about the dark sector

TL;DR

This paper explores how direct neutrino mass measurements could reveal properties of the dark sector, especially if neutrinos acquire mass through interactions involving dark matter particles, linking neutrino physics to dark matter models.

Contribution

It demonstrates that current experimental constraints on a scotogenic dark matter-neutrino coupling allow for a direct measurement of the lightest neutrino mass via KATRIN.

Findings

Linear dependence of neutrino mass on dark sector-Higgs coupling.

KATRIN could directly measure the neutrino mass in this scenario.

Constraints support the feasibility of probing dark sector interactions through neutrino experiments.

Abstract

Searches for Dark Matter suggest that it couples to ordinary matter only very weakly and possibly only through the Higgs or other scalar bosons. On the other hand, neutrinos might not couple to the Higgs boson directly, but only through a loop of Dark Matter particles, which would naturally explain the small neutrino masses. We demonstrate that current experimental constraints on such a ``scotogenic'' scenario allow to make the linear dependence of the lightest neutrino mass on the dark sector-Higgs coupling explicit, so that a measurement by the KATRIN experiment would directly determine its value.