Scalar $D^{(\ast )}{K}^{(\ast )}$ and $D^{(\ast )}\pi (\rho )$ molecular states from B meson decays

In this paper, we investigate the production of scalar singly charmed four-quark states from $B$ meson decays, employing phenomenological SU(3) flavor symmetry analysis and final-state interaction theory. Our study focuses on their production branching ratios and $CP$ violation. The results show that the branching ratios for producing either $VV$ or $PP$ molecular states from $B$ meson decays can be as large as the order of ${10}^{-4}$. Moreover, for processes with direct $CP$ violation, the production of $VV$ molecular states exhibits a sizable $CP$ asymmetry of order ${10}^{-3}$. Our findings also suggest that the recently observed $T_{\bar{c}\bar{s}0}^{\ast }(2870{)}^0$ state is more consistent with the ${\bar{D}}^{\ast 0}{K}^{\ast 0}$ molecular configuration. We expect that our predictions will be validated by future experiments.