Sep 15 – 21, 2019
Hotel Hermitage, La Biodola Bay, Isola d'Elba, Italy
Europe/Rome timezone

Single Shot High Transformer Ratio Measurements in the Nonlinear Plasma Regime

Sep 17, 2019, 5:00 PM
SML (Hotel Hermitage)


Hotel Hermitage

talk WG1 - Electron beams from plasmas WG1 - Plasma acceleration physics I


Gerard Andonian (UCLA)


We demonstrate the first single shot measurement of a multi-period, loaded PWFA wakefield, used to conduct measurements of the transformer ratio (TR), the ratio between the maximum accelerating and decelerating fields in a collinear wakefield accelerator, that far exceed previous measurements. The emittance exchange beamline at the Argonne Wakefield Accelerator was used to create a variable longitudinal drive profile with a long witness to sample multiple wakefield periods. A TR exceeding the limit of 2 for longitudinally asymmetric beams was observed for a linear ramp and wakefield flattening was observed for a beam with a parabolic head. These effects are important for efficient energy transfer from drive to witness beam, and for lengthening the interaction length of the process. Furthermore, by adjusting plasma density parameters, multi-period plasma wakefields were observed transitioning from linear to nonlinear regimes leading to experimental verification of theoretical wakefield properties. 3D Particle in cell simulations are used throughout to support the experimental findings.

Primary authors

Ryan Roussel (University of California Los Angeles) Gerard Andonian (UCLA) Dr Gwanghui Ha (Argonne National Laboratory) John Power (Argonne National Laboratory) Manoel Conde (Argonne National Laboratory) Dr Eric Wisniewski (Argonne National Laboratory) James Rosenzweig (UCLA)

Presentation materials