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Axion-like particles (ALPs) arise from well-motivated extensions to the Standard Model and could account for dark matter. ALP dark matter would manifest as a field oscillating at an (as of yet) unknown frequency. The frequency depends linearly on the ALP mass and plausibly ranges from 10−22to 10 eV/c2. This motivates broadband search approaches. We report on a direct search for ALP dark matter with an interferometer composed of two atomic K-Rb-3He comagnetometers, one situated in Mainz, Germany, and the other in Kraków, Poland. We leverage the anticipated spatio-temporal coherence properties of the ALP field and probe all ALP-gradient-spin interactions covering a mass range of nine orders of magnitude. No significant evidence of an ALP signal is found. We thus place new upper limits on the ALP-neutron, ALP-proton and ALP-electron couplings reaching belowgaNN < 10−9 GeV−1,gaPP < 10−7 GeV−1andgaee < 10−6 GeV−1, respectively. These limits improve upon previous laboratory constraints for neutron and proton couplings by up to three orders of magnitude.
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This content will become publicly available on May 1, 2027
Constraints on axion-like particles from ultra-high-energy observations of 3HWC J1908+063 with HAWC
Abstract Axion-like particles (ALPs) are hypothetical particles and compelling candidates for cold dark matter. Their existence could be probed through their conversions into photons in the presence of magnetic fields. In this work, we explore the effect of these photon-ALP conversions by searching for an attenuation in the observed gamma ray spectra of galactic sources that emit at energies of hundreds of TeV. We analyze data from the High-Altitude Water Cherenkov (HAWC) Observatory for the source 3HWC J1908+063. No evidence of photon-ALP conversions was found, and we set constraints on the ALP parameter space. Specifically, we derive exclusion limits for ALPs with masses in the range 10-8 eV ≤ma≤ 10-6 eV and photon-ALP couplings in the range 10-12 GeV-1≤gaγ≤ 10-10 GeV-1, based on HAWC observations.
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- PAR ID:
- 10700080
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- IOP Science Journal of Cosmology and Astroparticle Physics
- Date Published:
- Journal Name:
- Journal of Cosmology and Astroparticle Physics
- Volume:
- 2026
- Issue:
- 05
- ISSN:
- 1475-7516
- Page Range / eLocation ID:
- 024
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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