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arXiv · 2301.07365

Production of $X_b$ via $\Upsilon(5S, 6S)$ radiative decays

Xiao-Yun Wang·Zu-Xin Cai·Gang Li·Shi-Dong Liu·Chun-Sheng An·Ju-Jun Xie
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Abstract

We investigate the production of $X_b$ in the process $\Upsilon(5S,6S)\to \gamma X_b$, where $X_b$ is assumed to be a $B {\bar B}^*$ molecular state. Two kinds of meson loops of $B^{(*)}{\bar B}^{(*)}$ and $B_1^{\prime}{\bar B}^{(*)}$ were considered. To explore the rescattering mechanism, we calculated the relevant branching ratios using the effective Lagrangian based on the heavy quark symmetry. The branching ratios for the $\Upsilon(5S\,,6S) \to \gamma X_b$ were found to be at the orders of $10^{-7} \sim 10^{-6}$. Such sizeable branching ratios might be accessible at BelleII, which would provide important clues to the inner structures of the exotic state $X_b$.

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Xiao-Yun Wang, Zu-Xin Cai, Gang Li, Shi-Dong Liu, Chun-Sheng An, Ju-Jun Xie. 2023-01-18. Production of $X_b$ via $\Upsilon(5S, 6S)$ radiative decays. https://doi.org/10.1140/epjc%2Fs10052-023-11333-0

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