Constraints on axion-like particles from gamma-ray astronomy with H.E.S.S

Denis Wouters; Pierre Brun

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arXiv · 1304.0700

Constraints on axion-like particles from gamma-ray astronomy with H.E.S.S

Denis Wouters·Pierre Brun

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Abstract

Pseudoscalar particles like axion-like particles generically couple to two photons, giving rise to the possibility of oscillations with photons in an external magnetic field. These oscillations could lead to measurable imprints in the electromagnetic spectrum of astrophysical sources if the coupling to photons is strong enough. One possible signature is the presence of irregularities in a limited energy range of the spectrum. In this study, anomalous irregularities are searched for in the spectrum of the bright extragalactic TeV emitter PKS 2155-304 as measured by H.E.S.S. to put constraints on the coupling of light spin 0 particles to photons.

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Denis Wouters, Pierre Brun. 2013-04-02. Constraints on axion-like particles from gamma-ray astronomy with H.E.S.S. https://arxiv.org/abs/1304.0700

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