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arXiv · 2405.18215

Constraining axion-gluon coupling in monohadron processes

Shou-shan Bao·Wenhai Gao·Hong Zhang·Jian Zhou
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Abstract

The axion-gluon coupling can be constrained directly through hard exclusive processes at the LHC. Specifically, we study the associated production of a long-lived axion with a $\rho^0$ meson in ultra-peripheral $AA$ collisions and in $pp$ collisions. With the axion escaped from the detector, the final state is characterized by a mono-hadron signature. The main background in our analysis originates from the $\rho^0+\pi^0$ process, where the photons from the $\pi^0$ decay are undetected due to limited detector performance. Our analysis yields an exclusion limit of the axion-gluon coupling that is comparable to the limit obtained from the mono-jet process at the LHC.

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Shou-shan Bao, Wenhai Gao, Hong Zhang, Jian Zhou. 2024-05-28. Constraining axion-gluon coupling in monohadron processes. https://doi.org/10.1103/physrevd.110.055008

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