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arXiv · 2109.12920

Phenomenology of the companion-axion model: photon couplings

Zhe Chen·Archil Kobakhidze·Ciaran A. J. O'Hare·Zachary S. C. Picker·Giovanni Pierobon
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Abstract

We study the phenomenology of the 'companion-axion model' consisting of two coupled QCD axions. The second axion is required to rescue the Peccei-Quinn solution to the strong-CP problem from the effects of colored gravitational instantons. We investigate here the combined phenomenology of axion-axion and axion-photon interactions, recasting present and future single-axion bounds onto the companion-axion parameter space. Most remarkably, we predict that future axion searches with haloscopes and helioscopes may well discover two QCD axions, perhaps even within the same experiment.

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Zhe Chen, Archil Kobakhidze, Ciaran A. J. O'Hare, Zachary S. C. Picker, Giovanni Pierobon. 2021-09-27. Phenomenology of the companion-axion model: photon couplings. https://doi.org/10.1140/epjc/s10052-022-10909-6

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