Attosecond-scale dynamics in ion-atom collision versus laser-atom interaction

We compare the ionization process occurring during an ion-atom collision and the ionization process occurring during the interaction of the atom with two orthogonal radiation pulses. The envelope of the radiation pulses was chosen in order to mimic the electric field produced by the incoming ion during the collision process. We focus on the regime of intermediate velocities, where the projectile and the target electron velocities are of the same order, and discuss the similarities and the differences between the two processes.