Investigations on the light hadron decays of $Z_b(10610)$ and $Z_b(10650)$

Abstract

The light hadron decay processes of $Z_b(10610)/Z_b(10650)$ provide us a way to study their nature and decay mechanism. In this work, we evaluate the branching ratios of $Z_b(10610)/Z_b(10650)\to VP$ ($V$ and $P$ stand for light vector and pseudoscalar mesons, respectively) using an effective Lagrangian approach, in which the contributions of intermediate bottomed meson triangle loops are considered. In our calculations, the $Z_b(10610)$ and $Z_b(10650)$ are regarded as $B{\bar{B}}^{\ast }+c.c.$ and $B^{\ast }{\bar{B}}^{\ast }$ molecular states, respectively. The predicted branching ratios of $Z_b(10610)\to VP$ are about in the order of $10^{-2}$, while the branching ratios of $Z_b(10650)\to VP$ are in the order of $10^{-3}$. Furthermore, the dependence of these ratios between different decay modes of $Z_b(10610)/Z_b(10650)$ on the mixing $\eta -{\eta }^{\prime }$ angle ${\theta }_P$ is investigated, which may be a good quantity for the experiments. It is hoped that the calculations here could be tested by future experiments.

Comments: 7 pages, 8 figures and 1 table