Decays of doubly charmed meson molecules

Abstract

Several observed states close to the $D{\bar{D}}^{\ast }$ and $D_{(s)}^{\ast }{\bar{D}}_{(s)}^{\ast }$ thresholds, as the X(3872) and some XYZ particles can be described in terms of a two-meson molecule. Furthermore, doubly charmed states are also predicted. These new states are near the $D^{\ast }{D}^{\ast }$ and $D^{\ast }{D}_s^{\ast }$ thresholds, % Therefore, if the previous XYZ are molecules, then, there should be doubly charmed mesons with $J^P=1^{+}$ around the $D^{\ast }{D}^{\ast }$ threshold. %For this reason, it is important to evaluate observables related to them. Because of the spin$=1$, they do not decay into $DD$. In this article we compute decays to $D{D}^{\ast }$ and radiative decays of doubly charmed meson molecules into $D{D}_{(s)}{\hat{I}}^3$. and have spin-parity $J^P=1^{+}$. Their natural decay modes are $D_{(s)}{D}^{\ast }$, $D{D}_{(s)}\ddot{I}€$ and $D{D}_{(s)}{\hat{I}}^3$ and $D^{\ast }{D}_{(s)}{\hat{I}}^3$. We evaluate the widths of these states, named here as $R_{cc}(3970)$ and $S_{cc}(4100)$, and obtain 44 MeV for the non-strangeness, and 24 MeV for the doubly charm-strange state. Essentially, the decay modes are $D{D}_{(s)}\ddot{I}€$ and $D{D}_{(s)}{\hat{I}}^3$, being the $D\ddot{I}€$ and $D{\hat{I}}^3$ emitted by one of the $D^{\ast }$ meson which forms the molecule.

31 pages, 9 figures, 20 tables