Regularization of Coulomb potentials in the treatment of nonresonant transitions to an ionizing continuum

Close-coupling techniques often break down when transitions to a continuum or quasicontinuum cannot be neglected. This work describes an extension of a recently proposed method [L. F. Errea, L. M\'endez, and A. Riera, Chem. Phys. Lett. 164, 261 (1989)] to deal with such situations, when the coupling terms involve Coulomb potentials. A connection with the method of packet states is made, and a preliminary application of the method is presented.