ELECTRON TRAJECTORIES IN INTENSE LASER PULSES

Abstract

Collisions of short, intense laser pulses with electron beams have recently been proposed for various purposes, such as high-quality, Compton-Backscattered X-ray sources (CBX), or coherent pair production positron sources for future e{sup +}e{sup {minus}} Linear Colliders. For such intense laser fields, few-photon perturbative treatments do not suffice, and nonperturbative effects in the fields must be modeled. These effects have, until recently, only been modeled within the ''local plane wave'', or Volkov, approximation, in which ponderomotive (i.e. laser intensity gradient) effects are ignored. A systematic quantum treatment of the ''post-Volkov'' effects occurring in such collisions has recently been initiated by Ben-Menahem. In the present paper, we use the results of to render a simplified treatment of the leading ponderomotive corrections to electron trajectories during the electron-laser collision, and estimate the ramifications for CBX sources which utilize such collisions. We also apply to the CBX case some recently derived estimates of three non-ponderomotive effects: two body collisions in the laser-induced shower; EM self-forces of this shower; and back-reaction of linac-laser collisions upon the laser fields. All three effects are shown to be negligible for the numerical examples considered here.