Transition form factors for mesons containing heavy quarks

Transition form factors for hadrons containing heavy quarks are considered in the approach based on the analysis of Feynman diagrams. Partonic interpretation of the diagrams in the infinite-momentum frame is discussed. Expressions for the form factors valid in the entire accessible kinematical region of q2 are obtained. The heavy-quark symmetry relations are satisfied, and a single universal function, which determines all form factors for transitions between pseudoscalar and vector mesons, is calculated. 11 refs., 6 figs