  The recently observed color-suppressed B0bar to D0 pi0, D0 eta, D0 eta', Ds+
K-, D0 K0bar, D0 rho0 and D0 omega decay modes all have rates larger than
expected. The color-suppressed Bs to D0 phi, D0bar phi modes, which were
suggested for the extraction of the unitarity angle gamma in the Gronau-London
method, could be larger than the previous estimation by one order of magnitude.
Several new theoretical clean modes in Bs decays are suggested for the
extraction of gamma. The proposed Bs to D0 h0, D0bar h0 decay modes with h0 =
pi0, eta, eta', rho0, omega in addition to h0 = phi are free from penguin
contributions. Their decay rates can be estimated from the observed
color-suppressed B0bar to D0 h0 rates through SU(3) symmetry. A combined study
of these D0 h0, D0bar h0 modes in addition to the D0 phi, D0bar phi modes is
useful in the extraction of gamma in the Bs system without involving the
Bs-Bsbar mixing. Since the b to u and b to c transitions belong to the same
topological diagram, the relative strong phase is likely to be small. In this
case, the CP asymmetries are suppressed and the untagged rates are very useful
in the gamma extraction.

High Energy Physics - Phenomenology;High Energy Physics - Experiment