A Study of the Rare Decays B^0\to D_s^{(*)+} π^- and B^0\to D_s^{(*)-} K^+
Abstract
We report evidence for the decays B^0\to D_s^{+} \pi^- and B^0\to D_s^{-} K^+ and the results of a search for B^0 \to D_s^{*+} \pi^- and B^0\to D_s^{*-} K^+ in a sample of 84 milion Y(4S) decays into B\bar{B} pairs collected with the BaBar detector at the PEP II asymmetric-energy e^{+}e^{-} storage ring. We measure the branching fraction Br(B^0 \to D_s^{+} \pi^-) = 3.2 \pm 0.9 ({\rm stat.})\pm 1.0 ({\rm syst.}). and Br(B^0 \to D_s^{+} \pi^-) = 3.2 \pm 1.0 ({\rm stat.})\pm 1.0 ({\rm syst.}). We also set 90% C.L. limits BR(B^0 \to D_s^{*+} \pi^-) < 4.1\times 10^{-5} at 90% C.L and BR(B^0 \to D_s^{*-} K^+)< 2.5\times 10^{-5} at 90% C.L.