An isospin analysis of CP violation in Bd → Dπ, D∗π and Dϱ

By use of current experimental data, we carry out an isospin analysis of the weak decays B → Dπ, D∗π and Dϱ. It is found that only in B → Dϱ the strong phase shift of two different isospin amplitudes can be approximately neglected. We derive some useful relations between the CP-violating measurables and the weak and strong transition phases, and illustrate the different effects of final-state interactions on CP violation in Bd → Dπ, D∗π and Dϱ.