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arXiv · 1511.06743

9 GeV Energy Gain in a Beam-Driven Plasma Wakefield Accelerator

M Litos·E Adli·J M Allen·W An·C I Clarke·S Corde·C E Clayton·J Frederico·S J Gessner·S Z Green·M J Hogan·C Joshi·W. Lu·K A Marsh·W B Mori·M Schmeltz·N Vafaei-Najafabadi·V Yakimenko
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Abstract

An electron beam has gained a maximum energy of 9 GeV per particle in a 1.3 m-long electron beam-driven plasma wakefield accelerator. The amount of charge accelerated in the spectral peak was 28.3 pC, and the root-mean-square energy spread was 5.0%. The mean accelerated charge and energy gain per particle of the 215 shot data set was 115 pC and 5.3 GeV, respectively, corresponding to an acceleration gradient of 4.0 GeV/m at the spectral peak. The mean energy spread of the data set was 5.1%. These results are consistent with the extrapolation of the previously reported energy gain results using a shorter, 36 cm-long plasma source to within 10%, evincing a non-evolving wake structure that can propagate distances of over a meter in length. Wake-loading effects were evident in the data through strong dependencies observed between various spectral properties and the amount of accelerated charge.

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M Litos, E Adli, J M Allen, W An, C I Clarke, S Corde, C E Clayton, J Frederico, S J Gessner, S Z Green, M J Hogan, C Joshi, W. Lu, K A Marsh, W B Mori, M Schmeltz, N Vafaei-Najafabadi, V Yakimenko. 2015-11-20. 9 GeV Energy Gain in a Beam-Driven Plasma Wakefield Accelerator. https://doi.org/10.1088/0741-3335%2F58%2F3%2F034017

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