Study of $\overline{B}{}^0\rightarrow D^{+}h^{-} (h=K/\pi)$ decays at Belle

TL;DR

This paper reports precise measurements of branching fractions for specific B meson decays into D mesons and kaon or pion, using the full Belle dataset, providing insights into decay dynamics and CKM matrix elements.

Contribution

First precise measurement of branching fractions for ar;Bb0+hb7 decays at Belle, including ratio, using the full dataset.

Findings

Branching fraction of ar;Bb0+b7b7 decays: (2.48 b1 0.01 b1 0.09 b1 0.04) d7 10^{-3}

Branching fraction of ar;Bb0+b7Kb7 decays: (2.03 b1 0.05 b1 0.07 b1 0.03) d7 10^{-4}

Branching ratio R^{D} = (8.19 b1 0.20 b1 0.23) d7 10^{-2}

Abstract

We present a measurement of the branching fractions of the Cabibbo favored $\overline{B}{}^0\rightarrow D^{+}\pi^{-}$ and the Cabibbo suppressed $\overline{B}{}^0\rightarrow D^{+}K^{-}$ decays. We find $\mathcal{B}(\overline{B}{}^0\rightarrow D^{+}\pi^{-}) = (2.48 \pm 0.01 \pm 0.09 \pm 0.04) \times 10^{-3}$ and $\mathcal{B}(\overline{B}{}^0\rightarrow D^{+}K^{-})= (2.03 \pm 0.05 \pm 0.07 \pm 0.03) \times 10^{-4}$ decays, where the first uncertainty is statistical, the second is systematic, and the third uncertainty is due to the $D^{+} \rightarrow K^{-}\pi^{+}\pi^{+}$ branching fraction. The ratio of branching fractions of $\overline{B}{}^0\rightarrow D^{+}K^{-}$ and $\overline{B}{}^0\rightarrow D^{+}\pi^{-}$ is measured to be $R^{D} = [8.19 \pm 0.20(\rm stat) \pm 0.23(\rm syst)] \times 10^{-2} $. These measurements are performed using the full Belle data set, which corresponds to $772 \times 10^{6} B\overline{B} $ pairs.