A Lab-Scale Experiment for keV Sterile Neutrino Search

Abstract

We developed a simple small-scale experiment to measure the beta decay spectrum of H-3. The aim of this research is to investigate the presence of sterile neutrinos in the keV region. Tritium nuclei were embedded in a 1x1x1 cm(3) LiF crystal from the Li-6(n,alpha)H-3 reaction. The energy of the beta electrons absorbed in the LiF crystal was measured with a magnetic microcalorimeter at 40 mK. We report a new method of sample preparation, experiments, and analysis of H-3 beta measurements. The spectrum of a 10-hour measurement agrees well with the expected spectrum of H-3 beta decay. The analysis results indicate that this method can be used to search for keV-scale sterile neutrinos.