Undulator-type radiation of bunched charged particles in self-wakefield

Abstract

Radiation appearing when relativistic charged particles moves along a periodic structure without external fields is investigated. It is shown that nonsynchronous spatial harmonics of wakefields excited by bunched charged particles can give rise to the particle oscillatory motion that consequently generates the undulator-type radiation (UR). A theory of the undulator-type radiation emitted by ultrarelativistic charged particles in the self-wakefields is given. An analytical expression for the spontaneous UR power of the ultrarelativistic monochromatic charged bunch moving in a weakly corrugated axially-symmetrical waveguide is derived by the perturbation method. The parameter region, a particle number and particle energies at which the spontaneous UR power exceeds the wakefield power is analyzed.