To the origin of the difference of FSI phases in B→ππ and B→ρρ decays

The final state interactions (FSI) model in which soft rescattering of low mass intermediate states dominates is suggested. It explains why the strong interaction phases are large in the B-d -> pi pi channel and are considerably smaller in the B-d -> rho rho one. Direct CP asymmetries of B-d -> pi pi decays which are determined by FSI phases are considered as well. (C) 2007 Elsevier B.V. All rights reserved.