Generation of high-energy electron beams from a plasma with a downward density transition

Abstract

A short intense laser beam or an electron beam generates a wake wave when it propagates in a plasma, and the wake wave produces an ultrastrong electric field (> 1GV/m). When such a wake field passes a sharply-downward density transition, a significant amount of background plasma electrons can be trapped and accelerated to a high energy by the wake field. According to particle-in-cell simulations, the quality of the trapped particles is fairly good for most applications. This kind of self-trapping-based internal injection scheme may be able to provide a new way to develop next generation table-top high-energy accelerators. In this paper, some detailed 2-dimensional simulation results are presented, and the planned experiments at the Center for Advanced Accelerators are introduced.