Results on light dark matter particles with a low-threshold CRESST-II detector

TL;DR

This study reports on the CRESST-II cryogenic detector's ability to detect low-mass dark matter particles using a low energy threshold of 307 eV, significantly improving sensitivity in this mass range.

Contribution

It demonstrates that lowering the energy threshold enhances the detection sensitivity for light dark matter particles in direct detection experiments.

Findings

Extended sensitivity to sub-GeV dark matter masses.

Achieved a nuclear recoil energy threshold of 307 eV.

Proved the importance of low energy thresholds in dark matter searches.

Abstract

The CRESST-II experiment uses cryogenic detectors to search for nuclear recoil events induced by the elastic scattering of dark matter particles in CaWO$_4$ crystals. Given the low energy threshold of our detectors in combination with light target nuclei, low mass dark matter particles can be probed with high sensitivity. In this letter we present the results from data of a single detector module corresponding to 52 kg live days. A blind analysis is carried out. With an energy threshold for nuclear recoils of 307 eV we substantially enhance the sensitivity for light dark matter. Thereby, we extend the reach of direct dark matter experiments to the sub-region and demonstrate that the energy threshold is the key parameter in the search for low mass dark matter particles.