We propose to investigate the time modulation of radioisotope decays deep underground as a method to explore axion dark matter. In this work, we focus on the -decay of heavy isotopes and develop a theoretical description for the -dependence of -decay half-lives, which enables us to predict the time variation of -radioactivity in response to an oscillating axion dark matter background. To probe this scenario, we have recently constructed and installed a setup deep underground at the Gran Sasso Laboratory, based on the -decay of Americium-241. This prototype experiment, named RadioAxion-, will allow us to explore a broad range of oscillation's periods, from a micro-second up to one year, thus providing competitive limits on the axion decay constant across 13 orders of magnitude in the axion mass, ranging from eV to eV after one month of data collection, and down to eV after three years.

中文翻译：

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地下深处的阿尔法放射性作为轴子暗物质的探测器


我们建议研究地下深处放射性同位素衰变的时间调制，作为探索轴子暗物质的方法。在这项工作中，我们专注于重同位素的衰变，并对衰变半衰期的依赖性进行了理论描述，这使我们能够预测响应于振荡轴子暗物质背景的放射性的时间变化。为了探究这种情况，我们最近在格兰萨索实验室地下深处建造并安装了一个基于镅241衰变的装置。这个名为 RadioAxion- 的原型实验将使我们能够探索从微秒到一年的广泛振荡周期，从而为轴子质量中 13 个数量级的轴子衰变常数提供有竞争力的限制，范围数据收集一个月后从 eV 降至 eV，三年后降至 eV。