The effect of heavy-particle interaction on the behavior of the double differential ionization cross sections

Using an earlier method based on the three-particle Faddeev equations modified for the Coulomb potentials, we study the effect of interaction of the incident particles with the nucleus of the target atom on the double differential inonization cross sections. It is shown on the example of the helium-atom ionization that taking into account this interaction improves the agreement of the theory with experiment in a wide range of energies of the colliding particles.