Multiphoton static and polarization bremsstrahlung in collisions of charged particles with multiply-charged ions in a strong laser field

A universal analytic description of multiphoton bremsstrahlung, including the static and polarization bremsstrahlung channels, in the collision of charged particles with multiply-charged ions is obtained on the basis of a specified quantum/classical current for arbitrary ''quantum/classical'' motion of the incident particle. For the description of stimulated polarization bremsstrahlung, the method of equivalent Fermi photons and the Kramers electrodynamics method [V. I. Kogan, A. B. Kukushkin, and V. S. Lisitsa, Phys. Rep. 213, 1 (1992)] are generalized to multiphoton processes. The resulting description of stimulated polarization bremsstrahlung is valid over a broad range about resonance, where its contribution is the most significant. The regions of polarization predominance over the static channel are indicated, and examples of interaction between the static and polarization channels are given. (C) 1997 American Institute of Physics.