We study ionization in laser-assisted high-energy nonrelativistic ion-atom collisions and show that the low-energy angular differential electron spectrum may be enhanced by five orders of magnitude by an external field of strength less than 1/100 of the atomic field. With increasing strength of the assisting field, the energy spectrum develops a plateau with a characteristic cutoff. In the plateau region we predict distinct multiphoton peaks separated by the photon energy of the assisting field. In the present laser-assisted continuum-distorted-wave eikonal-initial-state theory, this effect may be related to the dynamics in the two-body electron-projectile subsystem. The laser-assisted distorted wave Born and first Born approximation do not account for the phase-distortion of the target electron by the incoming projectile and consequently the associated plateau, cutoff, and multiphoton features are not predicted by these latter theories.
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|State||Published - 25 Feb 2008|