Revisiting rescattering contributions to B ¯ $$ \overline{B} $$ (s) → D s ∗ M $$ {D}_{(s)}^{\left(\ast \right)}M $$ decays

Abstract Motivated by the reported discrepancies between experimental data and Standard Model predictions for the branching ratios of the color-allowed decays B ¯ $$ \overline{B} $$ 0 → D (*)+ K − and B ¯ s 0 $$ {\overline{B}}_s^0 $$ → D s ∗ + π − $$ {D}_s^{\left(\ast \right)+}{\pi}^{-} $$ , we study final-state rescattering effects on B ¯ $$ \overline{B} $$ (s) → D s ∗ P $$ {D}_{(s)}^{\left(\ast \right)}P $$ and B ¯ $$ \overline{B} $$ (s) → D (s) V, where P(V) is a light pseudoscalar (vector) meson. We consider quasi-elastic rescatterings in the framework of SU(3) and U(3) flavor symmetries, and find that the effects cannot explain the measured branching ratios of the color-allowed and color-suppressed decays simultaneously. We also perform global fits to the B ¯ $$ \overline{B} $$ (s) → D s ∗ P $$ {D}_{(s)}^{\left(\ast \right)}P $$ and B ¯ $$ \overline{B} $$ (s) → D (s) V data, allowing for new physics contributions to the Wilson coefficient a 1 associated with the color-allowed tree amplitudes. It is shown that the fits prefer a downward shift of O $$ \mathcal{O} $$ (10%) in a 1 even in the presence of the quasi-elastic rescattering contributions.