First search for dark photon dark matter with a MADMAX prototype

Abstract

We report the first result from a dark photon dark matter search in the mass range from $78.62$ to $83.95\hat{\mathrm{I}}¼\mathrm{eV}/c^2$ with a dielectric haloscope prototype for MADMAX (Magnetized Disc and Mirror Axion eXperiment). Putative dark photons would convert to observable photons within a stack consisting of three sapphire disks and a mirror. The emitted power of this system is received by an antenna and successively digitized using a low-noise receiver. No dark photon signal has been observed. Assuming unpolarized dark photon dark matter with a local density of $\ddot{I}{}_{\ddot{I}}‡=0.3GeV/c{\mathrm{m}}^3$ we exclude a dark photon to photon mixing parameter $\ddot{I}‡>2.7\times 10^{-12}$ over the full mass range and $\ddot{I}‡>1.1\times 10^{-13}$ at a mass of $80.57\hat{\mathrm{I}}¼\mathrm{eV}/c^2$ with a 95\% confidence level. This is the first physics result from a MADMAX prototype and exceeds previous constraints on $\ddot{I}‡$ in this mass range by up to almost three orders of magnitude.

v2 (Adapted to match published version. Fixed a mistake in the dark matter lineshape leading to a ~10% improvement in the limit)