Measurement of B -> D_s K pi branching ratios

Abstract

We report a measurement of the exclusive $B^{+}$ meson decay to the final state $D_s^{-}{K}^{+}{\pi }^{+}$ using $520\times 10^{6}B\bar{B}$ pairs collected near the ${\rm Y}(4S)$ resonance, with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. Using the $D_S^{-}\to \varphi {\pi }^{-}$ decay mode to reconstruct $D_s^{-}$ mesons, we obtain the branching fraction $\mathcal{B}(B^{+}\to D_s^{-}{K}^{+}{\pi }^{+})=(1.77_{-0.12}^{+0.12}(stat)\pm 0.16(syst)\pm 0.23(\mathcal{B}))\times 10^{-4}$. We also present preliminary results of a study of the two-body $D_{s}K$, $D_s\pi$ and $K\pi$ subsystems observed in this final state.

22 pages, 12 figures, submitted to the 2007 Lepton-Photon Symposium