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arXiv · 2607.12004

Bounds on axion-like particles from fully merged photons at the LHC

Simon Knapen
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Abstract

I show that, in the mass range $0.1\,\text{GeV} < m_a < 6\,\text{GeV}$, the strongest current bound on axion-like particles (ALPs) coupled to photons comes from very high energy $a\gamma$ production at the LHC. In this regime, the two photons from the ALP decay are collimated and reconstructed as a single photon.

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Simon Knapen. 2026-07-13. Bounds on axion-like particles from fully merged photons at the LHC. https://arxiv.org/abs/2607.12004

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