MADMAX: A new road to axion dark matter detection

TL;DR

MADMAX is a proposed experiment aiming to detect axion dark matter in the 40-400 μeV mass range, using layered dielectric materials to enhance axion-photon conversion, addressing a gap in current experimental searches.

Contribution

This paper introduces the MADMAX experimental concept and prototype results, extending axion search sensitivity to higher masses above 25 μeV.

Findings

Prototype measurements demonstrate feasibility of the dielectric layer approach.

MADMAX can potentially cover the QCD axion parameter space around 100 μeV.

The design significantly extends current axion detection capabilities.

Abstract

The axion is a hypothetical low-mass boson predicted by the Peccei-Quinn mechanism solving the strong CP problem. It is naturally also a cold dark matter candidate if its mass is below $\sim$\,1\,meV, thus simultaneously solving two major problems of nature. All existing experimental efforts to detect QCD axions focus on a range of axion masses below $\sim$\,25$\,\mu$eV. The mass range above $\sim$\,40$\,\mu$eV, predicted by modern models in which the Peccei-Quinn symmetry was restored after inflation, could not be explored so far. The MADMAX project is designed to be sensitive for axions with masses (40--400$)\,\mu$eV. The experimental design is based on the idea of enhanced axion-photon conversion in a system with several layers with alternating dielectric constants. The concept and the proposed design of the MADMAX experiment are discussed. Measurements taken with a prototype test setup are discussed. The prospects for reaching sensitivity enough to cover the parameter space predicted for QCD dark matter axions with mass in the range around 100\,$\mu$eV is presented.