Transition radiation from a plasma boundary

The transition radiation emitted by a point charge moving with a uniform velocity across a plane interface separating a half-space of plasma from another half-space of free space is investigated. The transition radiation is partly in the form of space waves and partly in the form of surface waves. The characteristics of these waves are discussed with the help of some typical numerical results. The surface-wave power is shown to be many orders larger than the space-wave power and near the surface-wave resonant frequency an increase in the particle velocity is found to decrease the surface-wave power.