The Phenomenology of Right Handed Neutrinos

TL;DR

This paper reviews the theoretical and experimental status of right-handed neutrinos, exploring their potential roles in explaining neutrino oscillations, dark matter, baryogenesis, and dark radiation across various mass ranges.

Contribution

It provides a comprehensive overview of recent phenomenological developments and constraints on right-handed neutrinos across multiple mass scales, highlighting new experimental and theoretical insights.

Findings

Right-handed neutrinos could explain neutrino oscillations and dark matter.

Constraints vary across mass ranges from eV to TeV.

Experimental tests are feasible for certain mass scenarios.

Abstract

Neutrinos are the only particles in the Standard Model of particle physics that have only been observed with left handed chirality to date. If right handed neutrinos exist, they could be responsible for several phenomena that have no explanation within the Standard Model, including neutrino oscillations, the baryon asymmetry of the universe, dark matter and dark radiation. After a pedagogical introduction, we review recent progress in the phenomenology of right handed neutrinos. We in particular discuss the mass ranges suggested by hints for neutrino oscillation anomalies and dark radiation (eV), sterile neutrino dark matter scenarios (keV) and experimentally testable theories of baryogenesis (GeV to TeV). We summarize constraints from theoretical considerations, laboratory experiments, astrophysics and cosmology for each of these.