Observation of ${\overline{B}}^0\to D_{sJ}^{*}(2317{)}^{+}{K}^{-}$ Decay

The decays ${\overline{B}}^0\to D_{sJ}^{+}{K}^{-}$ and ${\overline{B}}^0\to D_{sJ}^{-}{\pi }^{+}$ are studied for the first time. A significant signal is observed in the ${\overline{B}}^0\to D_{sJ}^{*}(2317{)}^{+}{K}^{-}$ decay channel with $\mathcal{B}\mathbf{(}{\overline{B}}^0\to D_{sJ}^{*}(2317{)}^{+}{K}^{-}\mathbf{)}\times \mathcal{B}\mathbf{(}{D}_{sJ}^{*}(2317{)}^{+}\to D_s^{+}{\pi }^0\mathbf{)}=({5.3}_{-1.3}^{+1.5}\pm 0.7\pm 1.4)\times {10}^{-5}$. No signals are observed in the ${\overline{B}}^0\to D_{sJ}^{*}(2317{)}^{-}{\pi }^{+}$, ${\overline{B}}^0\to D_{sJ}(2460{)}^{+}{K}^{-}$, and ${\overline{B}}^0\to D_{sJ}(2460{)}^{-}{\pi }^{+}$ decay modes, and upper limits are obtained. The analysis is based on a data set of $140{\mathrm{f}\mathrm{b}}^{-1}$ collected by the Belle experiment at the asymmetric $e^{+}{e}^{-}$ collider KEKB.

Figure 1

Diagrams describing ${\overline{B}}^0\to D_{sJ}^{+}{K}^{-}$ decay.

Figure 2

$\Delta E$ (left) and $\Delta M(D_{sJ})$ (right) distributions for ${\overline{B}}^0$ decays to (a) $D_{sJ}^{*}(2317{)}^{+}{K}^{-}$, (b) $D_{sJ}^{*}(2317{)}^{-}{\pi }^{+}$, (c) $D_{sJ}(2460{)}^{+}{K}^{-}$, and (d) $D_{sJ}(2460{)}^{-}{\pi }^{+}$. Tight requirements on $M_{\mathrm{b}\mathrm{c}}$ and $\Delta M(D_{sJ})$ (left) or $\Delta E$ (right) are applied; see the text.