Hidden-charm decays of $X(3915)$ and $Z(3930)$ as the P-wave charmonia

Abstract

In this work, we investigate the $X(3915)$ and $Z(3930)$ decays into $J/\psi \omega$ with the ${\chi }_{c0}^{\prime }(2P)$ and ${\chi }_{c2}^{\prime }(2P)$ assignments to $X(3915)$ and $Z(3930)$, respectively. The results show that the decay width of $Z(3930)\to J/\psi \omega$ is at least one order smaller than that of $X(3915)\to J/\psi \omega$. This observation explains why only one structure $X(3915)$ has been observed in the $J/\psi \omega$ invariant mass spectrum for the process $\gamma \gamma \to J/\psi \omega$.

Comments: 5 pages, 3 figures and 1 table