First search for axion dark matter with a Madmax prototype

Abstract

This paper presents the first search for dark matter axions with mass in the ranges 76.56 to 76.82 $\hat{I}¼$eV and 79.31 to 79.53 $\hat{I}¼$eV using a prototype setup for the MAgnetized Disk and Mirror Axion eXperiment (MADMAX). The experimental setup employs a dielectric haloscope consisting of three sapphire disks and a mirror to resonantly enhance the axion-induced microwave signal within the magnetic dipole field provided by the 1.6 T Morpurgo magnet at CERN. Over 14.5 days of data collection, no axion signal was detected. A 95% CL upper limit on the axion-photon coupling strength down to $|g_{a{\hat{I}}^3}|\sim 2\times 10^{-11}{\mathrm{GeV}}^{-1}$ is set in the targeted mass ranges, surpassing previous constraints, assuming a local axion dark matter density $\ddot{I}{}_a$ of $0.3\mathrm{GeV}/{\mathrm{cm}}^3$. This study marks the first axion dark matter search using a dielectric haloscope.