Testing the sterile neutrino dark matter paradigm with astrophysical observations

TL;DR

This paper reviews how sterile neutrino dark matter affects small-scale structure formation, compares production mechanisms, and discusses constraints and implications for dwarf galaxy abundance.

Contribution

It provides a comparative analysis of resonant and scalar decay production mechanisms of sterile neutrino dark matter and their astrophysical signatures.

Findings

Sterile neutrino dark matter can suppress small-scale structures.

Resonant production is constrained by structure formation data.

Scalar decay production offers alternative parameter space.

Abstract

Sterile neutrino dark matter is expected to suppress structure formation at small astrophysical scales. The details of the suppression depend on the sterile neutrino production mechanism in the early universe. In this proceeding, we focus on the most popular cases of resonant production (via the mixing between active and sterile neutrinos) and scalar decay production (via the decay of a hypothetical scalar singlet). We first review current constraints from structure formation before discussing how the sterile neutrino dark matter hypothesis can alleviate the overabundance problem of dwarf galaxies in the local universe.