Beam Physics Seminar

Friday, February 4, 2005, 9:30 AM
ARC, 231/233

General Theory of Intense Beam Nonlinear Thomson Scattering
Geoffrey Krafft

Table Top TeraWatt Lasers, which deliver very high laser energies in very short pulses, have become a mainstay in short time scale (< 100 fsec) studies of a wide variety. The intensity in such lasers is high enough that the wide variety of phenomena usually associated with high field strength undulaters, e.g. radiation red shifting and harmonic generation, become prominent features in the radiation spectra. In this talk I will first review my recent publication on pulsed beam backscattering where the laser and electron beams are in opposite directions, and generalize the calculation to include other scattering geometries; particularly those of 90 degree scattering and small angle Thomson scattering. The main qualitative differences in the results are that because part of the ponderomotive force from the laser is now directed transverse to the beam (this never happens in an undulater), strong dipole emission at the second harmonic occurs, oriented along the direction of laser incidence, and angular asymmetries in the frequency of emission arise. All of these effects can be computed exactly within the far-field limit, with a theory largely identical to that in the backscattering paper.

Talk Slides: (Slides)