Sterile Neutrino Dark Matter with Supersymmetry

TL;DR

This paper explores how supersymmetry introduces new features in sterile neutrino dark matter models, affecting their production and cosmological roles, including contributions to dark matter and relativistic degrees of freedom.

Contribution

It demonstrates that supersymmetry enables novel dark matter phenomena involving sterile neutrinos and their superpartners, expanding the theoretical landscape beyond non-supersymmetric models.

Findings

Sterile sneutrinos can dominate early Universe dark matter production.

Supersymmetry allows sterile neutrinos to contribute to Neff during nucleosynthesis.

New dark matter scenarios emerge from superpartner interactions.

Abstract

Sterile neutrino dark matter, a popular alternative to the WIMP paradigm, has generally been studied in non-supersymmetric setups. If the underlying theory is supersymmetric, we find that several interesting and novel dark matter features can arise. In particular, in scenarios of freeze-in production of sterile neutrino dark matter, its superpartner, the sterile sneutrino, can play a crucial role in early Universe cosmology as the dominant source of cold, warm, or hot dark matter, or of a subdominant relativistic population of sterile neutrinos that can contribute to the effective number of relativistic degrees of freedom Neff during Big Bang nucleosynthesis.