Improved Measurements of Color-Suppressed Decays B0bar -> D0 pi0, D0 eta, D0 omega, D*0 pi0, D*0 eta and D*0 omega

Abstract

We present improved measurements of the branching fractions of the color-suppressed decays ${\bar{B}}^0\to D^{(\ast )0}{h}^0$ where $h^0$ represents a light neutral meson $\ddot{I}{€}^0$, $\hat{I}\cdot$ or $\ddot{I}‰$. The measurements are based on a data sample of 140 $f{b}^{-1}$, collected at the $\hat{I}\yen (4S)$ resonance with the Belle detector at the KEKB energy-asymmetric $e^{+}{e}^{-}$ collider, corresponding to seven times the luminosity of the previous Belle measurements. All the measured branching fractions fall in the range 1.4-2.4 $\times 10^{-4}$, which is significantly higher than theoretical predictions based on naive factorization.

11 pages, 5 figures, KEK Preprint 2006-17, Belle Preprint 2006-20, minor changes : this version accepted for publication in Phys. Rev. D