Xing, ZZ (reprint author), Acad Sinica, Inst High Energy Phys, Beijing 100039, Peoples R China.
The first observation of the color-suppressed decay mode (B) over bar (0)(d)-->D((*)0)pi0 by the Belle and CLEO Collaborations makes a quantitative analysis of the isospin relations for the amplitudes of B-->D-(*) pi possible. The strong ( isospin) phase difference in B-->Dpi transitions is found to be about 29degrees by use of the Belle data or 26degrees by use of the CLEO data, implying that final-state interactions might not be negligible. Applying the factorization approximation to I = 3/2 and I = 1/2 isospin amplitudes of B-->Dpi decays, we obtain the ratio of the effective Wilson coefficients a(1)(eff) and a(2)(eff) : a(2)(eff)/a(1)(eff) approximate to 0.27. A similar analysis shows that the magnitude of final-state interactions in B-->D*pi might be comparable with that in B-->Dpi, and the factorization hypothesis works consistently in both of them.