Ablikim, M (reprint author), CCAST, World Lab, POB 8730, Beijing 100080, Peoples R China.
We study D --> pipi decays with final state interactions considered in one-particle-exchange method. A clear physical picture for final state interactions based on quark and hadronic level diagrams is presented, A strong phase is introduced for hadronic effective couplings, which is crucial for explaining the experimental data of D+ --> pi(+)pi(o), D-o --> pi(+)pi(-), and D-o --> pi(o)pi(o). Rescattering effects between different D decay channels are usually large. They are important for obtaining correct branching ratios for D --> pipi decays in theoretical calculation. (C) 2002 Elsevier Science B.V. All rights reserved.