Direct Neutrino Mass Experiments

TL;DR

This paper reviews the current status and future prospects of direct neutrino mass measurement experiments based on beta-decay kinematics, highlighting their importance for understanding physics beyond the Standard Model.

Contribution

It provides a comprehensive overview of direct neutrino mass experiments, discussing recent advancements and future experimental plans.

Findings

Current experiments set upper limits on neutrino mass.

Near-future experiments aim to improve sensitivity significantly.

Direct measurements complement cosmological and double beta-decay approaches.

Abstract

With a mass at least six orders of magnitudes smaller than the mass of an electron -- but non-zero -- neutrinos are a clear misfit in the Standard Model of Particle Physics. On the one hand, its tiny mass makes the neutrino one of the most interesting particles, one that might hold the key to physics beyond the Standard Model. On the other hand this minute mass leads to great challenges in its experimental determination. Three approaches are currently pursued: An indirect neutrino mass determination via cosmological observables, the search for neutrinoless double $\beta$-decay, and a direct measurement based on the kinematics of single $\beta$-decay. In this paper the latter will be discussed in detail and the status and scientific reach of the current and near-future experiments will be presented.