Neutrino-less Double Beta Decay and Particle Physics

TL;DR

This paper reviews the particle physics mechanisms behind neutrino-less double beta decay, exploring standard and non-standard interpretations, their potential to reveal new physics, and methods to distinguish among various theoretical models.

Contribution

It provides a comprehensive overview of all proposed mechanisms for neutrino-less double beta decay, including new theoretical models and experimental strategies to differentiate them.

Findings

Summarizes the physics potential of standard and non-standard decay mechanisms.

Discusses methods to distinguish different decay mechanisms.

Highlights the importance of future measurements for understanding particle physics.

Abstract

We review the particle physics aspects of neutrino-less double beta decay. This process can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). The physics potential of both interpretations is summarized and the consequences of future measurements or improved limits on the half-life of neutrino-less double beta decay are discussed. We try to cover all proposed alternative realizations of the decay, including light sterile neutrinos, supersymmetric or left-right symmetric theories, Majorons, and other exotic possibilities. Ways to distinguish the mechanisms from one another are discussed. Experimental and nuclear physics aspects are also briefly touched, alternative processes to double beta decay are discussed, and an extensive list of references is provided.