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RadioAxion results on the search for axion dark matter under Gran Sasso

Carlo Broggini1,*, Giuseppe Di Carlo2,†, Luca Di Luzio1,‡, Denise Piatti1,§, and Claudio Toni3,∥

  • *Contact author: carlo.broggini@pd.infn.it
  • †Contact author: giuseppe.dicarlo@lngs.infn.it
  • ‡Contact author: luca.diluzio@pd.infn.it
  • §Contact author: denise.piatti@pd.infn.it
  • ∥Contact author: claudio.toni@lapth.cnrs.fr
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Phys. Rev. D 113, 112007 – Published 15 June, 2026

DOI: https://doi.org/10.1103/198x-z7c3

Abstract

We report first results from RadioAxion, an underground experiment searching for axion dark matter through periodic modulations of radioisotope decays. We monitor the α decay of Am241 via its 59.5 keV γ line using a NaI detector installed at the Gran Sasso Laboratory, where cosmic-ray-induced systematics are strongly suppressed. We present the measured spectra and the corresponding time-series analysis. No evidence for a periodic modulation is observed. From these data, we derive constraints on the axion decay constant in the axion mass range from 10−21 to 10−9  eV.

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Weak nuclear decays deep-underground as a probe of axion dark matter

Jorge Alda, Carlo Broggini, Giuseppe Di Carlo, Luca Di Luzio, Denise Piatti, Stefano Rigolin, and Claudio Toni
Phys. Rev. D 111, 035022 (2025)

Article Text

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Outline

Information

Phys. Rev. D 113, 112007– Published 15 June, 2026
  • Received 26 February 2026
  • Accepted 13 May 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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