Hadronic B decays to open charm at the BaBar Experiment

TL;DR

This paper reports measurements of branching fractions for various B meson decays to open charm using data from the BaBar experiment, providing insights into decay modes relevant for CP violation studies.

Contribution

First measurement of several B decay modes to open charm with detailed branching fractions, enhancing understanding of B decay dynamics and CP violation parameters.

Findings

Branching fraction for B^0 → D^{*-} D^{0} K^+ is (2.8 ± 0.7 ± 0.5)×10^{-3}

Branching fraction for B^0 → D^{*-} D^{*0} K^+ is (6.8 ± 1.7 ± 1.7)×10^{-3}

Observation of B^+ → D^{*+} D^{*-} K^+ with a branching fraction of (3.4 ± 1.6 ± 0.9)×10^{-3}

Abstract

Using about 23M $B \bar B$ events collected in 1999-2000 with the BABAR detector, we report on the decays $B \to D^{(*)}\bar D^{(*)}K$ and $B^0 \to D^{*+}D^{*-}$. The branching fractions of the low background decay modes $B \to D^{(*)}\bar D^{(*)}K$ are determined to be ${\cal B}(B^0 \to D^{*-}D^{0}K^+) = (2.8 \pm 0.7 \pm 0.5)\times 10^{-3}$ and ${\cal B}(B^0 \to D^{*-}D^{*0}K^+) = (6.8 \pm 1.7 \pm 1.7)\times 10^{-3}$, where the first error quoted is statistical and the second systematic. Observation of a significant number of candidates in the color-suppressed decay mode $B^+\to D^{*+}D^{*-}K^+$ is reported with a branching fraction ${\cal B}(B^+\to D^{*+}D^{*-}K^+)= (3.4\pm 1.6\pm 0.9)\times 10^{-3}$. Decays of the type $B \to D^{(*)} \bar D^{(*)}$ can be used to provide a measurement of the parameter $\sin 2 \beta$ of the Unitarity Triangle. For this decay mode we measure a branching fraction of ${\cal BR} (B^0 \to D^{*+}D^{*-}) = (8.0 \pm 1.6\pm 1.2)\times 10^{-4}$. All results presented here are preliminary.