Ion-motion simulations of a plasma-wakefield experiment at FLASHForward

TL;DR

This paper uses simulations to explore how ion motion affects plasma wakefield acceleration experiments, highlighting the importance of considering ion dynamics for accurate modeling and experimental observation.

Contribution

It presents the first detailed simulation study of ion motion effects in beam-driven plasma wakefield experiments at FLASHForward, emphasizing observable signatures.

Findings

Ion motion can cause emittance growth in plasma wakefields.

Simulations predict observable effects in FLASHForward experiments.

Ion dynamics are significant for accurate modeling of plasma accelerators.

Abstract

In plasma-based acceleration, an ultra-relativistic particle bunch$\unicode{x2014}$or an intense laser beam$\unicode{x2014}$is used to expel electrons from its propagation path, forming a wake that is devoid of electrons. The ions, being significantly more massive, are often assumed to be stationary. However, both theory and simulations suggest that any sufficiently dense electron bunch can trigger ion motion, and its effect must be taken into account. We simulate beam-driven plasma wakefields to identify key features$\unicode{x2014}$such as longitudinally dependent emittance growth$\unicode{x2014}$that could be observed in an experiment using plasma and beam parameters from the FLASHForward facility at DESY.