Probing $D_{s0}^{\ast }(2317)$ in the decays of $B$ to two charmed mesons

Abstract

We probe the inner structure of the meson $D_{s0}^{\ast }(2317)$ through the decays of $B_{(s)}$ to two charmed mesons within pQCD approach. Assuming $D_{s0}^{\ast }(2317)$ as a scalar meson with $\bar{c}s$ structure, we find that the predictions for the branching ratios of the decays $B^{+}\to D_{s0}^{\ast +}(2317){\bar{D}}^{(\ast )0},B^0\to D_{s0}^{\ast +}(2317)D^{(\ast )-}$ can explain data within errors. The branching ratios for the decays $B_s\to D_{s0}^{\ast +}(2317)D_s^{(\ast )+}$ are estimated to reach up to $10^{-3}$ order, which can be observed by the present LHCb and SuperKEKB experiments. In this work, the decay constant of the meson $D_{s0}^{\ast }(2317)$ is an input parameter. Unfortunately, its value has been studied by many references but with large uncertainties. Our calculation shows that a smaller decay constant of the meson $D_{s0}^{\ast }(2317)$ is supported by compared with the present data, say $55\sim 70$ MeV. We also calculate the ratios $R_1=\frac{Br(B^{+}\to D_{s0}^{\ast +}(2317){\bar{D}}^0)}{Br(B^{+}\to D_{s0}^{\ast +}(2317){\bar{D}}^{\ast 0})})$ and $R_2=\frac{Br(B^0\to D_{s0}^{\ast +}(2317)D^{-})}{Br(B^0\to D_{s0}^{\ast +}(2317)D^{\ast -})}$, which are valuable to determine the inner structure of $D_{s0}^{\ast }(2317)$ by compared with the experimental results. Our predictions for the ratios $R_{1,2}$ are consistent with the present data within errors.We expect that these two ratios can be well measured by the future experiments through improving the measurement accuracy for the decays $B^{+}\to D_{s0}^{\ast +}(2317){\bar{D}}^{\ast 0}$ and $B^0\to D_{s0}^{\ast +}(2317)D^{\ast -}$.

Comments: 19 pages, 2 figures