Electron–ion collisions in strong electromagnetic fields

The current status of the problem of electron–ion collisions in strong electromagnetic fields is presented. The collision operator is expressed in terms of an integral over test particle trajectories for an arbitrary alternating field. The equation for test particles is analyzed. It is shown that none of the energy processes involved (Joule heating, bremsstrahlung and fast electron generation) diminishes as the electromagnetic field amplitude increases. The collision frequency, the momentum distribution of fast electrons, and the electron–ion collision operator are calculated in the classical framework.