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arXiv · 2007.12639

Controlled density-downramp injection in a beam-driven plasma wakefield accelerator

Alexander Knetsch·Bridget Sheeran·Lewis Boulton·Pardis Niknejadi·Kristjan Põder·Lucas Schaper·Ming Zeng·Simon Bohlen·Gregory Boyle·Theresa Brümmer·James Chappell·Richard D'Arcy·Severin Diederichs·Brian Foster·Matthew James Garland·Pau Gonzalez Caminal·Bernhard Hidding·Vladislav Libov·Carl Andreas Lindstrøm·Alberto Martinez de la Ossa·Martin Meisel·Trupen Parikh·Bernhard Schmidt·Sarah Schröder·Gabriele Tauscher·Stephan Wesch·Paul Winkler·Jonathan Wood·Jens Osterhoff
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Abstract

This paper describes the utilization of beam-driven plasma wakefield acceleration to implement a high-quality plasma cathode via density-downramp injection in a short injector stage at the FLASHForward facility at DESY. Electron beams with charge of up to 105 pC and energy spread of a few percent were accelerated by a tunable effective accelerating field of up to 2.7 GV/m. The plasma cathode was operated drift-free with very high injection efficiency. Sources of jitter, the emittance and divergence of the resulting beam were investigated and modeled, as were strategies for performance improvements that would further increase the wide-ranging applications for a plasma cathode with the demonstrated operational stability

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Alexander Knetsch, Bridget Sheeran, Lewis Boulton, Pardis Niknejadi, Kristjan Põder, Lucas Schaper, Ming Zeng, Simon Bohlen, Gregory Boyle, Theresa Brümmer, James Chappell, Richard D'Arcy, Severin Diederichs, Brian Foster, Matthew James Garland, Pau Gonzalez Caminal, Bernhard Hidding, Vladislav Libov, Carl Andreas Lindstrøm, Alberto Martinez de la Ossa, Martin Meisel, Trupen Parikh, Bernhard Schmidt, Sarah Schröder, Gabriele Tauscher, Stephan Wesch, Paul Winkler, Jonathan Wood, Jens Osterhoff. 2020-07-24. Controlled density-downramp injection in a beam-driven plasma wakefield accelerator. https://doi.org/10.1103/physrevaccelbeams.24.101302

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