Charged-particle scattering in the presence of an external electromagnetic field

Charged particle scattering in the presence of an external electromagnetic field is investigated theoretically. The so called space translation method is applied to the description of three different types of scattering; namely to the scattering of identical particles, of particles with opposite charge but equal mass, and to inverse bremstrahlung. The effect of the particles' spins is also considered. The main conclusion is that no net particle acceleration is possible in the scattering process of identical particles in the presence of an external field. To obtain net acceleration it is necessary that one particle should be heavy or that the particles should have charges of opposite sign. An order of magnitude estimation is also given for the relative role of the higher order processes on the scattering. (Sz.Z.)