Finite-t and target mass corrections to deeply virtual Compton scattering on a scalar target

Using the recently developed formalism we carry out the first complete calculation of kinematic power corrections to the helicity amplitudes of deeply-virtual Compton scattering to the twist-four accuracy for a study case of a (pseudo) scalar target. Our main result is that both finite-t, similar to t/Q(2), and target mass, similar to m(2)/Q(2), twist-four kinematic power corrections turn out to be factorizable, at least to the leading order in the strong coupling. The structure of these corrections is discussed and a short model study of their numerical impact is presented.