Wakefield regeneration in a resonantly driven plasma accelerator

TL;DR

This paper demonstrates a method to increase luminosity in plasma wakefield accelerators by using a train of drive bunches to accelerate multiple witness bunches in a single shot, effectively doubling the accelerated charge.

Contribution

It introduces a novel technique of periodically loading wakefields with a train of drive bunches to enhance energy transfer and luminosity in plasma accelerators.

Findings

Doubling of the accelerated charge achieved in simulations.

Periodic loading removes the limit on energy transfer.

Technique exploits only a fraction of the drive train.

Abstract

Plasma wakefields offer high acceleration gradients, orders of magnitude larger than conventional RF accelerators. However, the achievable luminosity remains relatively low, typically limited by repetition rate and the charge accelerated per shot. In this work, we show that a train of drive bunches can be harnessed to accelerate multiple witness bunches in a single shot. We demonstrate that periodically loading the wakefields removes the limit on the energy transfer from the drive beam to the plasma, which allows the luminosity to be increased. Proof-of-concept simulations for the AWAKE scheme are carried out to demonstrate the technique, achieving a doubling of the accelerated charge while exploiting only a fraction of the drive train.