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arXiv · 2509.20583

Permanently magnetized axion-photon conversion surface for direct dark matter searches with BRASS-p

Le Hoang Nguyen·Dieter Horns·Andrei Lobanov
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Abstract

A new method was recently proposed for axion dark matter searches which employs scalable, permanently magnetized, flat conversion surface (or magnetized converter) generating an electromagnetic signal from dark matter particles passing through them. BRASS-p is an experimental setup which applies this method to direct searches of axion/ALP dark matter in the frequency range from 12 to 18 GHz (corresponding to the range of particle mass from 50 to 74 $\mu$eV. The conversion surface of BRASS-p will consist of 24 individual panels, each containing a 483mm $\times$ 483mm array of high-grade permanent magnets organized in a pattern capable of generating a magnetic field with an average strength of $\approx$ 0.9 T, for the field component parallel to the surface of the panel. This paper describes the development and optimization of a design for these panels and discusses the resulting sensitivity of BRASS-p measurements to the axion/ALP dark matter.

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Le Hoang Nguyen, Dieter Horns, Andrei Lobanov. 2025-09-24. Permanently magnetized axion-photon conversion surface for direct dark matter searches with BRASS-p. https://arxiv.org/abs/2509.20583

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