Transition form factors between pseudoscalar and vector mesons in light-front dynamics

We study the transition form factors between pseudoscalar and vector mesons using a covariant fermion field theory model in [Formula Presented] dimensions. Performing the light-front calculation in the [Formula Presented] frame in parallel with the manifestly covariant calculation, we note that the suspected nonvanishing zero-mode contribution to the light-front current [Formula Presented] does not exist in our analysis of transition form factors. We also perform the light-front calculation in a purely longitudinal [Formula Presented] frame and confirm that the form factors obtained directly from the timelike region are identical to the ones obtained by the analytic continuation from the spacelike region. Our results for the [Formula Presented] decay process satisfy the constraints on the heavy-to-heavy semileptonic decays imposed by the flavor independence in the heavy quark limit.