Isospin and a possible interpretation of the newly observedX(1576)

Abstract

Recently, the BES Collaboration observed a broad resonant structure $X(1576)$ with a large width being around 800 MeV and assigned its ${J}^{PC}$ number to ${1}^{--}$. We show that the isospin of this resonant structure should be assigned to 1. This state might be a molecule state or a tetraquark state. We study the consequences of a possible ${K}^{*}(892)\ensuremath{-}\overline{\ensuremath{\kappa}}$ molecular interpretation. In this scenario, the broad width can easily be understood. Carefully searching this resonant structure in the $J/\ensuremath{\psi}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ and $J/\ensuremath{\psi}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ decays should be important for understanding the structure of $X(1567)$.