Direct determination of Neutrino Mass from Tritium Beta Spectrum

TL;DR

This paper discusses the direct measurement of neutrino mass through the analysis of the tritium beta decay spectrum's endpoint, highlighting past experiments and the upcoming KATRIN project aiming for higher sensitivity.

Contribution

It introduces the KATRIN experiment, which will significantly improve neutrino mass measurement sensitivity compared to previous experiments.

Findings

Previous experiments reached 2 eV/c^2 sensitivity.

KATRIN aims to reach 0.2 eV/c^2 sensitivity.

The method is crucial for understanding neutrino mass scale.

Abstract

The investigation of the endpoint region of the tritium beta decay spectrum is still the most sensitive direct method to determine the neutrino mass scale. In the nineties and the beginning of this century the tritium beta decay experiments at Mainz and Troitsk have reached a sensitivity on the neutrino mass of 2 eV/c^2 . They were using a new type of high-resolution spectrometer with large sensitivity, the MAC-E-Filter, and were studying the systematics in detail. Currently, the KATRIN experiment is being set up at Forschungszentrum Karlsruhe, Germany. KATRIN will improve the neutrino mass sensitivity by one order of magnitude down to 0.2 eV/c^2, sufficient to cover the degenerate neutrino mass scenarios and the cosmologically relevant neutrino mass range.