Implications of Bbar to D0 h0 Decays on Bbar to D Kbar, Dbar Kbar Decays
  The recently observed color suppressed B0bar to D0 pi0, D0 eta, D0 eta', Ds+ K-and D0 K0bar decay modes all have rates larger than expected, hinting at the presence of final state interactions. We study rescattering effects in Bbar to D P, D Kbar and Dbar Kbar modes in the quasi-elastic approach, which is extended to accommodate D0 eta' without using U(3) symmetry. The D0bar Kbar modes are of interest in the determination of the unitarity angle phi3/gamma. The updated DP data are used to extract the effective Wilson coefficients a_1^{eff} ~ 0.92, a_2^{eff} ~ 0.22, three strong phases delta ~ 62 deg., theta ~ 24 deg., sigma ~ 127 deg., and the mixing angle tau~2 deg. The values of delta and theta are close to our previous results. The smallness of tau implies small mixing of D0 eta1 with other modes. Predictions for D0 K-, D+ K- and D0 K0bar agree with data. The framework applies to Bbar to Dbar Kbar decays, and rates for D0bar K-, D- K0, Ds- pi0, Ds- eta and Ds- eta' modes are predicted.   From B- to D0bar K- and D0 K- rates, we find r_B=0.09\pm 0.02. 
Chun-Khiang Chua, Wei-Shu Hou