Particle scattering in the presence of a spatially inhomogeneous laser field

The influence on charged-particle scattering of a spatially inhomogeneous laser field with a Gaussian distribution over the transverse coordinate is investigated. Considerable reduction of the cross section is found for weak fields or when many photons are exchanged while enhancement is found instead for processes where few photons are exchanged. The results reported permit useful insights into the multiphoton free-free transition experiments of Weingartshofer et al. (Phys. Rev. A.; 19:2371 (1979) and Phys. Rev. Lett.; 39:269 (1977)). (author)