A Plasma Wave Accelerator - Surfatron II

Abstract

Particles may be accelerated to arbitrarily high energy as they ride across the wave fronts. This paper describes this phenomenon for the Surfatron 1. The limitation on the total energy gain possible with recent plasma accelerator schemes such as the beat-wave accelerator of Tajima and Dawson is overcome by the Surfatron. By introducing a perpendicular magnetic field it is possible to keep particles in phase with the laser-induced plasma waves and hence accelerate them to arbitrarily high energy. The beat-wave accelerator is one scheme proposed by Dawson and Tajima to excite large amplitude electrostatic plasma waves which can accelerate particles. The authors have shown that classical particles trapped by a perpendicularly propagating electrostatic wave are accelerated until they de-trap near the E x B. (cE/B). In this paper it is considered that the relativistic effects introduced when the E x B velocity is greater than the speed of light and when the wave's phase velocity is not small compared to c. The authors treat the trapped particle motion analytically and numerically, followed by application of these results to the beat wave example. Considered is a plane wave electric field and uniform magnetic field.