Analysis of the X(1835) and related baryonium states with Bethe-Salpeter equation

Abstract.

In this article, we study the mass spectrum of the baryon-antibaryon bound states p $\bar{{p}}$ , $\Sigma$ $\bar{{\Sigma}}$ , $\Xi$ $\bar{{\Xi}}$ , $\Lambda$ $\bar{{\Lambda}}$ , p $\bar{{N}}$(1440) , $\Sigma$ $\bar{{\Sigma}}$(1660) , $\Xi$ $\bar{{\Xi}}^{{\prime}}_{}$ and $\Lambda$ $\bar{{\Lambda}}$(1600) with the Bethe-Salpeter equation. The numerical results indicate that the p $\bar{{p}}$ , $\Sigma$ $\bar{{\Sigma}}$ , $\Xi$ $\bar{{\Xi}}$ , p $\bar{{N}}$(1440) , $\Sigma$ $\bar{{\Sigma}}$(1660) , $\Xi$ $\bar{{\Xi}}^{{\prime}}_{}$ bound states maybe exist, and the new resonances X(1835) and X(2370) can be tentatively identified as the p $\bar{{p}}$ and p $\bar{{N}}$(1440) (or N(1400)$\bar{{p}}$ bound states, respectively, with some gluon constituents, and the new resonance X(2120) may be a pseudoscalar glueball. On the other hand, the Regge trajectory favors identifying the X(1835) , X(2120) and X(2370) as the excited $\eta^{{\prime}}_{}$(958) mesons with the radial quantum numbers n = 3 , 4 and 5, respectively.