Dark-Photon Search using Data from CRESST-II Phase 2

TL;DR

This paper reports new constraints on dark photons, a dark matter candidate, using data from the CRESST-II Phase 2 experiment, improving previous limits for certain mass ranges.

Contribution

It provides the first constraints on dark-photon kinetic mixing from CRESST-II data in the 0.3 to 0.7 keV/c² mass range.

Findings

Improved constraints on dark-photon kinetic mixing for masses 0.3-0.7 keV/c².

Analysis of 52 kg-days of CRESST-II Phase 2 data.

Demonstrates sensitivity of direct detection experiments to dark photons.

Abstract

Identifying the nature and origin of dark matter is one of the major challenges for modern astro and particle physics. Direct dark-matter searches aim at an observation of dark-matter particles interacting within detectors. The focus of several such searches is on interactions with nuclei as provided e.g. by Weakly Interacting Massive Particles. However, there is a variety of dark-matter candidates favoring interactions with electrons rather than with nuclei. One example are dark photons, i.e., long-lived vector particles with a kinetic mixing to standard-model photons. In this work we present constraints on this kinetic mixing based on data from CRESST-II Phase 2 corresponding to an exposure before cuts of 52\,kg-days. These constraints improve the existing ones for dark-photon masses between 0.3 and 0.7\,keV/c$^2$.