Rearrangement collisions in the presence of a laser field.

Abstract

The formal quantum-mechanical treatment of rearrangement collisions in the presence of a strong laser field is developed. The analysis is restricted to structureless projectiles, hydrogenic target atoms, and a homogeneous, single-mode linearly polarized laser field, taken in the dipole approximation. The external field is found to interfere with the rearrangement process through several mechanisms, some of which are not present in field-assisted direct collisions. One new parameter comes from the difference of continuum Stark shifts. A second parameter relating to the transfer of the electron arises from a field-dependent shift of the particle momentum. The familiar notions of exothermic and endothermic reactions appear in a new perspective; namely, they transform into the reactions able to yield prevalently either emission or absorption of laser photons.