Sterile Neutrinos, Coherent Scattering and Oscillometry Measurements with Low-temperature Bolometers

TL;DR

This paper explores the use of optimized cryogenic bolometers with extremely low energy thresholds to detect coherent neutrino-nucleon scattering, aiming to investigate the existence of light sterile neutrinos through oscillometry measurements.

Contribution

It introduces an optimized design for cryogenic bolometers capable of detecting very low-energy neutrino interactions, enhancing sensitivity to sterile neutrino oscillations.

Findings

Reactor data analysis suggests sterile neutrinos with specific mass splitting and mixing.

Low-threshold bolometers can potentially confirm or refute sterile neutrino existence.

The proposed detector array could provide definitive results on sterile neutrino hypotheses.

Abstract

Coherent neutrino-nucleon scattering offers a unique approach in the search for physics beyond the Standard Model. When used in conjunction with mono-energetic neutrino sources, the technique can be sensitive to the existence of light sterile neutrinos. The ability to utilize such reactions has been limited in the past due to the extremely low energy threshold (10-50 eV) needed for detection. In this paper, we discuss an optimization of cryogenic solid state bolometers that enables reaching extremely low kinetic energy thresholds. We investigate the sensitivity of an array of such detectors to neutrino oscillations to sterile states. A recent analysis of available reactor data appears to favor the existence of such such a sterile neutrino with a mass splitting of $|\Delta m_{\rm sterile}|^2 \ge 1.5$ eV$^2$ and mixing strength of $\sin^2{2\theta_{\rm sterile}} = 0.17\pm 0.08$ at 95% C.L. An array of such low-threshold detectors would be able to make a definitive statement as to the validity of the interpretation.