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arXiv · hep-ph/9807363

Constraints on Axion Models from $K^+\toπ^+ a$

Mark Hindmarsh·Photis Moulatsiotis
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Abstract

We explore a new class of axion models in which some, but not all, of the left-handed quarks have a Peccei-Quinn symmetry. These models are potentially afflicted by flavour changing neutral currents. We derive the bounds on the Peccei-Quinn symmetry-breaking scale from bounds on the $K^+\to π^+ a$ branching ratio, showing that in some cases they are even stronger than the astrophysical ones, but still not strong enough to kill off the models.

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Mark Hindmarsh, Photis Moulatsiotis. 1998-12-16. Constraints on Axion Models from $K^+\toπ^+ a$. https://doi.org/10.1103/physrevd.59.055015

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