Search for $CP$ Violation in the Decay ${B}^{0}\ensuremath{\rightarrow}{D}^{*\ifmmode\pm\else\textpm\fi{}}{D}^{\ensuremath{\mp}}$

Search for $C P$ Violation in the Decay $B^{0} \to D^{* \pm} D^{\mp}$

T. Aushev et al. (Belle Collaboration)

Phys. Rev. Lett. 93, 201802 – Published 9 November 2004

Abstract

We report a search for $C P$ -violating asymmetry in $B^{0} \to D^{* \pm} D^{\mp}$ decays. The analysis employs two methods of $B^{0}$ reconstruction: full and partial. In the full reconstruction method all daughter particles of the $B^{0}$ are required to be detected; the partial reconstruction technique requires a fully reconstructed $D^{-}$ and only a slow pion from the $D^{* +} \to D^{0} π_{s l o w}^{+}$ decay. From a fit to the distribution of the time interval corresponding to the distance between two $B$ meson decay points we calculate the $C P$ -violating parameters and find the significance of nonzero $C P$ asymmetry to be 2.7 standard deviations.