X(1870) and $\eta_2(1870)$: Which can be assigned as a hybrid state?

Understand

The mass spectrum and strong decays of the X(1870) and $\eta_2(1870)$ are analyzed.

• Our results indicate that X(1870) and $\eta_2(1870)$ are the two different resonances.
• The narrower X(1870) seems likely a good hybrid candidate.
• We support the $\eta_2(1870)$ as the $\eta_2(2^1D_2)$ quarkonium.