SELF-CONSISTENT ANALYSIS OF 3D UNDULATOR RADIATION AND RELATIVISTIC ELECTRON-BEAM DYNAMICS USING LIENARD-WIECHERT FIELDS

Lienard-Wiechert (LW) fields, which are exact solutions of the wave eq uation for a point charge in free space, and the Lorentz force equatio ns are employed to formulate a self-consistent treatment of electron b eam dynamics and radiation field evolution in magnetic undulators. In a relativistic electron beam the internal forces leading to the intera ction of the electrons with each other can be computed by means of ret arded LW fields. The resulting electron motion enables us to obtain th ree dimensional undulator radiation by summing up the field contributi on of each electron in the beam. The approach used is particularly wel l suited to the investigation of self amplified spontaneous emission ( SASE) without introducing a seed wave at start-up. In this paper, we p resent studies of non-periodic multi-bucket electron phase dynamics as well as temporal and angular characteristics of the electromagnetic f ields radiated by a relativistic short filamentary electron beam inter acting with a circularly polarized magnetic undulator.