LAUSR

We investigate the process of ${\mathrm{\ensuremath{\Lambda}}}_{b}\ensuremath{\rightarrow}\mathrm{\ensuremath{\Lambda}}D\overline{D}$, by taking into account the contributions from the $s$-wave $D\overline{D}$ interaction within the coupled-channel unitary approach, and the intermediate $\ensuremath{\psi}(3770)$ resonance. In addition to the peak of the $\ensuremath{\psi}(3770)$, an enhancement near the $D\overline{D}$ mass threshold is found in the $D\overline{D}$ invariant mass distributions, which should be the reflection of the $D\overline{D}$ bound state. We encourage our experimental colleagues to measure the $D\overline{D}$ invariant mass distribution of the ${\mathrm{\ensuremath{\Lambda}}}_{b}\ensuremath{\rightarrow}\mathrm{\ensuremath{\Lambda}}D\overline{D}$ process, which is crucial to search for the $D\overline{D}$ bound state and to understand the heavy-hadron heavy-hadron interactions.