Maximizing the Efficiency of Plasma-based Lepton Accelerators

Future plasma accelerators for high-energy physics or industrial applications will need to efficiently transfer energy from the driver into the witness bunch. Beam break-up instabilities may prevent this, but those models are based on assumptions that treat the plasma bubble as a conducting beam pipe, which must be validated. Using advanced algorithms for modeling plasmas, we will adapt the wake field model to plasma accelerators and determine if and where the model remains valid. We will also work to mitigate remaining wake or wake-like instabilities to allow plasma accelerators to be operated efficiently.During Phase I, we will determine if these advanced plasma modeling algorithms can correctly capture the conventional picture of wake fields in plasma systems, and then use the benchmarked tools to calculate the wake fields in a plasma accelerator. We will then determine when the standard wake field picture applies, and how it breaks down. This will inform Phase II work to mitigate any remaining instabilities and enable high-efficiency plasma accelerators. Efficiency is important for many plasma accelerator applications, including as bright X-ray sources for national security or drivers for TeV colliders or extremely compact free-electron lasers. The developments from this project will allow those applications to operate at significantly reduced power cost.