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arXiv · 2506.04144

Could an axion-like particle be hidden in $\eta_c\to\gamma\gamma$?

Zhi-Jun Li·Zheng-Yun You·Xiao-Rui Lyu
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Abstract

We discuss the possibility of an axion-like particle being merged in the recent observation of $\eta_c \to \gamma\gamma$ at BESIII and find that it cannot be excluded in the current experimental data. The mass, width, and coupling strengths of the axion-like particle are extracted, and several other channels to confirm or exclude the existence of such an axion-like particle are also discussed.

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Zhi-Jun Li, Zheng-Yun You, Xiao-Rui Lyu. 2025-06-04. Could an axion-like particle be hidden in $\eta_c\to\gamma\gamma$?. https://arxiv.org/abs/2506.04144

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