Search for exclusive two body decays $B \rightarrow {D_s}^{*} h$ at Belle

We report results of a search for $B^0 \rightarrow {D_s}^{*+} \pi^-$, $B^+ \rightarrow {D_s}^{*+} \pi^0$ and $\bar B^0 \rightarrow {D_s}^{*+} K^-$ in data collected at the $\Upsilon (4S)$ resonance by the Belle detector at the KEKB $e^+ e^-$ collider. $B^0 \rightarrow {D_s}^{*+} \pi^-$ and $B^+ \rightarrow {D_s}^{*+} \pi^0$ decays may be used to measure the magnitude of the CKM matrix element $V_{ub}$. The rate for the process $B^0 \rightarrow D_s^* \pi^+$ can be related to that for the process $B^0 \rightarrow D^{*+ }\pi^-$. The latter is needed to extract $\sin(2 \phi_1 + \phi_3)$ from a measurement of time-dependent CP asymmetries in $B \to D^* \pi$ decays. $\bar B^0 \rightarrow {D_s}^{*+} K^-$ decays may provide information on W-exchange diagrams and final state interactions. This search was performed using $2.75 \times 10^8$ $B \bar B$ pairs.