Proper Waves in Flows of Charged Particles

Abstract

Up to this point it has been assumed that individual charged particles interact only via their collective radiation field. That is, the short–range interaction via Coulomb fields has been neglected. However, it is physically evident that this approach is justified in the only case of low–density beams. As regards many modern microwave devices, the Coulomb interaction must be taken into account (especially in the high–current electronics). In these cases, Coulomb fields can exert substantial influence on the process of grouping charged particles into bunches emitting coherent radiation. At least, even the trivial Coulomb ‘repulsion’ of charged particles in an inhomogeneous beam exerts influence on the processes of the beam spatial modulation.