Production of the $X_b$ in $\Upsilon(5S, 6S)\to \gamma X_b$ radiative decays

TL;DR

This paper investigates the production of the hypothetical bottomonium-like state $X_b$ in radiative decays of $S$ and $S$, predicting small but potentially observable production ratios that could shed light on its structure.

Contribution

It introduces a theoretical calculation of $X_b$ production ratios in bottomonium decays using heavy quark symmetry and rescattering mechanisms, providing predictions for future experimental tests.

Findings

Production ratios are around 10^{-5} for $S,6S$ decays.

Predicted ratios are within reach of future experiments like BelleII.

Results support the molecular interpretation of $X_b$ as a $B ar{B}^*$ state.

Abstract

In this work, we investigate the production of $X_b$ in the process $\Upsilon(5S,6S)\to \gamma X_b$, where $X_b$ is assumed to be the counterpart of $X(3872)$ in the bottomonium sector as a $B {\bar B}^*$ molecular state. We use the effective Lagrangian based on the heavy quark symmetry to explore the rescattering mechanism and calculate their production ratios. Our results have shown that the production ratios for the $\Upsilon(5S,6S) \to \gamma X_b$ are orders of $10^{-5}$ with reasonable cutoff parameter range $\alpha \simeq 2\sim 3$. The sizeable production ratios may be accessible at the future experiments like forthcoming BelleII, which will provide important clues to the inner structures of the exotic state $X_b$.