How Many Dark Neutrino Sectors Does Cosmology Allow?

TL;DR

This paper constrains the number of dark neutrino sectors compatible with cosmological data and explores their potential to account for dark matter, providing new limits on models with multiple neutrino copies.

Contribution

It offers the first cosmological constraints on the number of dark neutrino sectors and demonstrates their viability as dark matter candidates.

Findings

Strong limits on the number of dark neutrino sectors from cosmology

Dark sectors can produce stable particles matching dark matter density

Constraints exclude large regions of parameter space

Abstract

We present the very first constraints on the number of Standard Model (SM) copies with an additional Dirac right-handed neutrino. From cosmology, we are able to pose strong limits on large regions of the parameter space. Moreover, we show that it is possible to account for the right dark matter density in form of stable particles from the dark sectors.