Multi-gigaelectronvolt acceleration of positrons in a self-loaded plasma wakefield

Journal Article · Wed Aug 26 00:00:00 EDT 2015 · Nature (London)

DOI:https://doi.org/10.1038/nature14890· OSTI ID:1213192

Corde, Sebastien ^[1]; Adli, E. ^[2]; Allen, J. M. ^[1]; An, W. ^[3]; Clarke, C. I. ^[1]; Delahaye, J. P. ^[1]; Frederico, J. ^[1]; Gessner, S. ^[1]; Green, S. Z. ^[1]; Hogan, M. J. ^[1]; Joshi, C. ^[3]; Lipkowitz, N. ^[1]; Litos, M. ^[1]; Lu, W. ^[4]; Marsh, K. A. ^[3]; Mori, W. B. ^[3]; Schmeltz, M. ^[1]; Vafaei-Najafabadi, N. ^[3]; Walz, D. ^[1]; Yakimenko, V. ^[1] ; Yocky, G. ^[1]; Clayton, C. E. ^[3]

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1. SLAC National Accelerator Lab., Menlo Park, CA (United States)
2. SLAC National Accelerator Lab., Menlo Park, CA (United States); Univ. of Oslo, Oslo (Norway)
3. Univ. of California, Los Angeles, CA (United States)
4. Tsinghua Univ., Beijing (China)

New accelerator concepts must be developed to make future particle colliders more compact and affordable. The Plasma Wakefield Accelerator (PWFA) is one such concept, where the electric field of a plasma wake excited by a charged-particle bunch is used to accelerate a trailing bunch of particles. To apply plasma acceleration to particle colliders, it is imperative that both the electrons and their antimatter counterpart, the positrons, are efficiently accelerated at high fields using plasmas1. While substantial progress has recently been reported on high-field, high-efficiency acceleration of electrons in a PWFA powered by an electron bunch 2, such an electron-driven wake is unsuitable for the acceleration and focusing of a positron bunch. Here we demonstrate a new regime of PWFA where particles in the front of a single positron bunch transfer their energy to a substantial number of those in the rear of the same bunch by exciting a wakefield in the plasma. In the process, the accelerating field is altered – self-loaded – so that about a billion positrons gain five gigaelectronvolts (GeV) of energy with a narrow energy spread in a distance of just 1.3 meters. They extract about 30% of the wake’s energy and form a spectrally distinct bunch with as low as a 1.8% r.m.s. energy spread. This demonstrated ability of positron-driven plasma wakes to efficiently accelerate a significant number of positrons with a small energy spread may overcome the long-standing challenge of positron acceleration in plasma-based accelerators.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 1213192
• Report Number(s): SLAC-PUB-16246
• Journal Information: Nature (London), Vol. 524, Issue 7566; ISSN 0028-0836
• Publisher: Nature Publishing Group
• Country of Publication: United States
• Language: English

Related Subjects

ACCPHY
PHYS
plasma-based accelerators
nonlinear phenomena