  This paper is focused on showing that the fully differential cross section of
ionization during a collision of a proton and an antiproton with a hydrogen
atom is directly expressed by the wave function in the coordinate
representation. Wave function is converted from impact parameter representation
to momentum transfer representation. In this case, the calculated wave function
corresponds at a certain projectile angle of scattering. The square
representation of this wave function module shows how the angular distribution
of ionized electrons varies over time. The ionized electron's flow is directly
visible from the image. In addition, the direct differentiation of the fully
differential ionization cross section by the wave function is shown to be
consistent with the effective time determined by the ionization amplitude,
which is the traditional method.
