The current status of "Troitsk nu-mass" experiment in search for sterile neutrino

TL;DR

This paper proposes a new experiment at Troitsk nu-mass to search for sterile neutrinos in the keV range by detecting spectral kinks in tritium beta-decay, aiming to significantly improve existing bounds.

Contribution

It introduces a novel experimental setup and methodology to enhance sensitivity in sterile neutrino searches at Troitsk nu-mass.

Findings

Potential to improve bounds on sterile neutrino mixing by an order of magnitude

Implementation of upgrades can further enhance detection sensitivity

Feasibility of precise spectrum measurements below the beta-decay endpoint

Abstract

We propose a new experiment to search for a sterile neutrino in a few keV mass range at the "Troitsk nu-mass" facility. The expected signature corresponds to a kink in the electron energy spectrum in tritium beta-decay. The new goal compared to our previous experiment will be precision spectrum measurements well below end point. The experimental installation consists of a windowless gaseous tritium source and a high resolution electromagnetic spectrometer. We estimate that the current bounds on the sterile neutrino mixing parameter can be improved by an order of magnitude in the mass range under 5 keV without major upgrade of the existing equipment. Upgrades of calibration, data acquisition and high voltage systems will allow to improve the bounds by another order of magnitude.