Heavy-strange meson molecules and possible candidates $D_{s0}^{\ast }(2317)$, $D_{s1}(2460)$, and $X_0(2900)$

Abstract

In this work, we systematically investigate the heavy-strange meson systems, $D^{(\ast )}{K}^{(\ast )}/{\bar{B}}^{(\ast )}{K}^{(\ast )}$ and ${\bar{D}}^{(\ast )}{K}^{(\ast )}/B^{(\ast )}{K}^{(\ast )}$, to study possible molecules in a quasipotenial Bethe-Salpter equation approach together with the one-boson exchange model. The potential is achieved with the help of the hidden-gauge Lagrangians. Molecular states are found from all six $S$-wave isoscalar interactions of $D^{(\ast )}{K}^{(\ast )}$ or ${\bar{B}}^{(\ast )}{K}^{(\ast )}$. The charmed-strange mesons $D_{s0}^{\ast }(2317)$ and $D_{s1}(2460)$ can be related to the $DK$ and $D^{\ast }K$ states with spin parities $0^{+}$ and $1^{+}$, respectively. In the current model, the $\bar{B}{K}^{\ast }$ molecular state with $1^{+}$ is the best candidate of the recent observed $B_{sJ}(6158)$. Four molecular states are produced from the interactions of ${\bar{D}}^{(\ast )}{K}^{(\ast )}$ or $B^{(\ast )}{K}^{(\ast )}$. The relation between the ${\bar{D}}^{\ast }{K}^{\ast }$ molecular state with $0^{+}$ and the $X_0(2900)$ is also discussed. No isovector molecular states are found from the interactions considered. The current results are helpful to understand the internal structure of $D_{s0}^{\ast }(2317)$, $D_{s1}(2460)$, $X_0(2900)$, and new $B_{sJ}$ states. The experimental research for more heavy-strange meson molecules is suggested.

8 pages,5 figure