First search for dark photon dark matter with a MADMAX prototype

TL;DR

This paper reports the first experimental search for dark photon dark matter using a MADMAX prototype, setting new constraints on the dark photon-photon mixing parameter in the 78.62 to 83.95 μeV/c^2 mass range.

Contribution

It presents the first results from a MADMAX dielectric haloscope prototype, improving constraints on dark photon dark matter in a specific mass range.

Findings

No dark photon signal detected.

Excluded mixing parameter  > 2.7  10^{-12} at 95% CL.

Improved previous constraints by up to three orders of magnitude.

Abstract

We report the first result from a dark photon dark matter search in the mass range from ${78.62}$ to $83.95~\mathrm{\mu eV}/c^2$ 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 $\rho_{\chi}=0.3~\mathrm{GeV/cm^3}$ we exclude a dark photon to photon mixing parameter $\chi > 2.7 \times 10^{-12}$ over the full mass range and $\chi > 1.1 \times 10^{-13}$ at a mass of $80.57~\mathrm{\mu eV}/c^2$ with a 95\% confidence level. This is the first physics result from a MADMAX prototype and exceeds previous constraints on $\chi$ in this mass range by up to almost three orders of magnitude.