Strong and radiative decays of theDs0*(2317)meson in theDK-molecule picture

Abstract

We consider a possible interpretation of the new charm-strange meson ${D}_{s0}^{*}(2317)$ as a hadronic molecule---a bound state of $D$ and $K$ mesons. Using an effective Lagrangian approach, we calculate the strong ${D}_{s0}^{*}\ensuremath{\rightarrow}{D}_{s}{\ensuremath{\pi}}^{0}$ and radiative ${D}_{s0}^{*}\ensuremath{\rightarrow}{D}_{s}^{*}\ensuremath{\gamma}$ decays. A new impact related to the $DK$ molecular structure of the ${D}_{s0}^{*}(2317)$ meson is that the presence of $u(d)$ quarks in the $D$ and $K$ mesons gives rise to a direct strong isospin-violating transition ${D}_{s0}^{*}\ensuremath{\rightarrow}{D}_{s}{\ensuremath{\pi}}^{0}$ in addition to the decay mechanism induced by $\ensuremath{\eta}\ensuremath{-}{\ensuremath{\pi}}^{0}$ mixing considered previously. We show that the direct transition dominates over the $\ensuremath{\eta}\ensuremath{-}{\ensuremath{\pi}}^{0}$ mixing transition in the ${D}_{s0}^{*}\ensuremath{\rightarrow}{D}_{s}{\ensuremath{\pi}}^{0}$ decay. Our results for the partial decay widths are consistent with previous calculations.