Dark photon constraints from a 7.139 GHz cavity haloscope experiment

Abstract

The dark photon is a promising candidate for the dark matter which comprises most of the matter in our visible Universe. Via kinetic mixing with the Standard Model it can also be resonantly converted to photons in an electromagnetic cavity, offering novel experimental possibilities for the discovery and study of dark matter. We report the results of a pathfinder dark photon dark matter cavity search experiment performed at Hunan Normal University and the Institute of Physics, Chinese Academy of Sciences, representing the first stage of the Axion and dark Photon EXperiment program. Finding no statistically significant excess, we place an upper limit on the kinetic mixing parameter |χ|<3.7×10−13 around mA≃29.5  μeV at 90% confidence level. This result exceeds other constraints on dark photon dark matter in this frequency range by roughly an order of magnitude. Published by the American Physical Society 2024