Klein-Gordon equation in a coupled channels description of elastic and inelastic scattering

We show that, in contrast to the case of elastic scattering of spinless particles from composite targets, Klein-Gordon dynamics is not a natural choice for the description of their inelastic scattering in the standard coupled channels method. We propose one way to overcome the difficulty, showing that Klein-Gordon dynamics may be used in practical calculations within the coupled channels framework provided that the optical potential is modified in a straightforward manner.