X(1835), X(2120), X(2370) and $\eta(1760)$ in chiral quark model
  By analyzing the meson spectra obtained in the constituent quark model, we find that the pseudoscalar mesons $\eta'(2^1S_0)$, $\eta(4^1S_0)$, $\eta'(3^1S_0)$ and $\eta'(4^1S_0)$ are the possible candidates of $\eta(1760)$, X(1835), X(2120) and X(2370). The strong decay widths of these pseudoscalars to all the possible decay modes are calculated within the framework of the $^3P_0$ model. Although the total width of $\eta'(2^1S_0)$ is compatible with the experimental value of BES for $\eta(1760)$, the partial decay width to $\omega\omega$ is too small, which is not consistent with the result of BES. If the state X(1835) is interpreted as $\eta(4^1S_0)$, the total decay width is compatible with the experimental data, and the main decay modes will be $\pi a_0(980)$ and $\pi a_0(1450)$, which needs to be checked. The assignment of X(2120) and X(2370) to $\eta'(3^1S_0)$ and $\eta'(4^1S_0)$ is also disfavored in the present calculation because of the incompatibility of the decay widths. 
Shaona Chen, Jialun Ping
hep-ph