Strong and Electromagnetic Decays of X(1835) as a Baryonium State
  With the assumption that the recently observed X(1835) is a baryonium state we have studied the strong decays of $X(1835) \to \eta^{(\prime)} \pi^+ \pi^-, \eta^{(\prime)} \pi^0 \pi^0$ and the electromagnetic decay of $X(1835) \to 2\gamma$ in the framework of effective Lagrangian formalism. In the present investigation we have included the contributions from the iso-singlet light scalar resonances but we have not included the isospin violating effect. Our result for the strong decay of $X(1835) \to \eta^{\prime} \pi^+ \pi^-$ is smaller than the observed data. The decay width for the radiative decay of $X(1835) \to 2\gamma$ is consistent with the assumption that it decays through the glueball. In addition, the width for the strong decay of $X(1835) \to \eta \pi^+ \pi^-$ is larger than that of the strong decay of $X(1835) \to \eta^{\prime} \pi^+ \pi^-$ due to the large phase space and coupling constant $g_{N\bar{N}\eta}$. From our investigation, it is not possible to interpret X(1835) as a baryonium. 
Yong-Liang Ma