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arXiv · 2508.08402

Sweeping the pion chimney for axion-like particles with KOTO

Reuven Balkin·Stefania Gori·Dean J. Robinson·Christiane Scherb
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Abstract

We demonstrate that novel limits on prompt axion-like particles (ALPs) in the hard-to-probe mass range near the neutral pion - the so-called pion chimney - may be obtained from recasting $K_L \to 3\pi^0 \to 6\gamma$ data taken by the J-PARC KOTO experiment, to search for $K_L \to 2\pi^0a \to 6\gamma$. We also explore the power of KOTO $6\gamma$ data to probe $K_L \to 2\pi^0a$ for a broader range of ALP masses, incorporating displaced decays.

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Reuven Balkin, Stefania Gori, Dean J. Robinson, Christiane Scherb. 2025-08-11. Sweeping the pion chimney for axion-like particles with KOTO. https://doi.org/10.1103/hpzj-v6dl

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