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arXiv · 2412.02543

Bounds on Axions-Like Particles Shining in the Ultra-Violet

Elisa Todarello·Marco Regis
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Abstract

Axion-like particles (ALPs) can decay into two photons with a rest-frame frequency given by half of the ALP mass. This implies that ultra-violet searches can be used to investigate ALPs in the multi-eV mass range. We use archival data from the Hubble Space Telescope between 110 and 170 nm to constrain ALPs with mass between 14.4-22.2 eV. We consider observations of a set of dwarf spheroidal galaxies and galaxy clusters and assume the ALP density in these objects to follow their dark matter density. The derived limit on the ALP-photon coupling $g_{a\gamma}$ excludes values above $10^{-12}~{\rm GeV}^{-1}$ over the whole mass range and surpasses previous limits by over one order of magnitude.

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Elisa Todarello, Marco Regis. 2024-12-03. Bounds on Axions-Like Particles Shining in the Ultra-Violet. https://arxiv.org/abs/2412.02543

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