The $D_{s0}^{\ast }(2317{)}^{+}$ decay to $D_s^{+}{\pi }^0$ and $D_s^{\ast +}\gamma$

Abstract

We study the strong decay of $D_{s0}^{\ast }(2317{)}^{+}$ to $D_s^{+}{\pi }^0$ considering the coupled channels of $D^0{K}^{+},D^{+}{K}^0,D_s^{+}\eta$ and $D_s^{+}{\pi }^0$ within a picture for the interaction based on the local hidden gauge approach. We also address the problem of the radiative decay to $D_s^{\ast +}\gamma$, using the same information obtained from the molecular picture. We obtain a strong width of the $D_{s0}^{\ast }(2317{)}^{+}$ of about $77\mathrm{keV}$ from coupled channels interaction and a radiative decay of about $1.7\mathrm{keV}$. We also show that the extra consideration of ${\pi }^0-\eta$ mixing can double the strong decay width to values around $140\mathrm{keV}$. The anomalous terms for the radiative decay are considered for the first time, but they are found negligible. We make a thorough discussion of this and other results to the light of the recent measurement of Belle for the ratio of these two decay modes, and make a call for the precise measurement of the two decay widths independently to clarify the present situation concerning the nature of the $D_{s0}^{\ast }(2317{)}^{+}$ state.

Comments: 12 pages, 7 figures, 3 tables; V2: new references added; V3: discussions added, version published in Eur. Phys. J. C