Possibility of a multibunch plasma afterburner for linear colliders

Abstract

A concept for increasing the energy of a multibunch linear collider using plasma wakefields is examined. The realization of high beam quality and high efficiency (and high luminosity) requires more complexity than the original plasma afterburner concept proposed for doubling the energy of single bunch linear colliders. This paper discusses the possibilities of using alternate bunches in the train to drive the wake and accelerate upon it or alternately a few bunches to excite the wake and a single bunch to accelerate it. Simulation results indicate that an energy of collision/energy of linac ratio of 2.8 can be obtained with 4% energy spread and 0.29 relative luminosity by utilizing five drive bunches per accelerated bunch. The concept including transverse effects is modeled with 2D linear plasma wakefield theory.