Probes of Heavy Sterile Neutrinos

TL;DR

This paper reviews experimental methods for detecting heavy sterile neutrinos, emphasizing the significance of their nature in neutrinoless double beta decay and discussing current constraints and future prospects.

Contribution

It provides a comprehensive overview of experimental probes for heavy sterile neutrinos and discusses the impact of their nature on neutrinoless double beta decay interpretations.

Findings

Current constraints on active-sterile mixing are stringent.

Future experiments will explore parameter regimes related to active neutrino lightness.

The nature of sterile neutrinos critically affects decay search interpretations.

Abstract

We review probes of heavy sterile neutrinos, focusing on direct experimental searches and neutrinoless double beta decay. Working in a phenomenological parametrization, we emphasize the importance of the nature of sterile neutrinos in interpreting neutrinoless double beta decay searches. While current constraints on the active-sterile neutrino mixing are already stringent, we highlight planned future efforts that will probe regimes motivated by the lightness of active neutrinos.