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arXiv · 1909.00005

Constraining axion-like particles from rare pion decays

Wolfgang Altmannshofer·Stefania Gori·Dean J. Robinson
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Abstract

Ultraviolet completions for axion-like particles (ALPs) lighter than the neutral pion generically induce ALP-neutral pion mixing, and are therefore sensitive to direct constraints on the mixing angle. For ALPs below the pion mass, we demonstrate that strong and novel bounds on the ALP-pion mixing angle can be extracted from existing rare pion decay data, measured by the PIENU and PIBETA experiments.

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Wolfgang Altmannshofer, Stefania Gori, Dean J. Robinson. 2019-08-30. Constraining axion-like particles from rare pion decays. https://doi.org/10.1103/physrevd.101.075002

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