High-quality positron acceleration in beam-driven plasma accelerators

Acceleration of positron beams in plasma-based accelerators is a highly challenging task. To realize a plasma-based linear collider, acceleration of a positron bunch with high-efficiency is required, while maintaining both a low emittance and a subpercent-level energy spread. Recently, a plasma-based positron acceleration scheme was proposed in which a wake suitable for the acceleration and transport of positrons is produced in a plasma column by means of an electron drive beam [Diederichs et al., Phys. Rev. Accel. Beams 22, 081301 (2019)PRABCJ2469-988810.1103/PhysRevAccelBeams.22.081301]. In this article, we present a study of beam loading for a positron beam in this type of wake. We demonstrate via particle-in-cell simulations that acceleration of high-quality positron beams is possible, and we discuss a possible path to achieve collider-relevant parameters.