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

Abstract

Abstract We investigate the production of $$X_b$$ X b in the process $$\Upsilon (5S,6S)\rightarrow \gamma X_b$$ Υ ( 5 S , 6 S ) → γ X b , where $$X_b$$ X b is assumed to be a $$B {\bar{B}}^*$$ B B ¯ ∗ molecular state. Two kinds of meson loops of $$B^{(*)}{\bar{B}}^{(*)}$$ B ( ∗ ) B ¯ ( ∗ ) and $$B_1^{\prime }{\bar{B}}^{(*)}$$ B 1 ′ 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 $$\Upsilon (5S,6S) \rightarrow \gamma X_b$$ Υ ( 5 S , 6 S ) → γ X b were found to be at the orders of $$10^{-7} \sim 10^{-6}$$ 10 - 7 ∼ 10 - 6 . Such sizeable branching ratios might be accessible at BelleII, which would provide important clues to the inner structures of the exotic state $$X_b$$ X b .