Speaker
Min Chen
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/O3.201.pdf
Plasma channel based new laser wakefield staging scheme
and radiation source
J. Luo1,7, M. Chen1,7, W. Y. Wu1,7, S. M. Weng1,7, Z. M. Sheng1,2,5,6,7, C. B. Schroeder3, D. A.
Jaroszynski2,6, E. Esarey3, W. P. Leemans3, W. B. Mori4, and J. Zhang1,7
1
Key Laboratory for Laser Plasmas (MOE), School of Physics and Astronomy,
Shanghai Jiao Tong University, Shanghai 200240, China
2
SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG, UK
3
Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
4
University of California, Los Angeles, CA 90095, USA
5
Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
6
Cockcroft Institute, Sci-Tech Daresbury, Cheshire WA4 4AD, UK
7
Collaborative Innovation Centre of IFSA (CICIFSA), Shanghai Jiao Tong University,
Shanghai 200240, China
Multistage coupling of laser-wakefield accelerators with independent driving laser
pulses is essential to overcome laser energy depletion for high energy applications such as
the TeV level electron-positron collider. Currently a staging scheme is achieved by feeding a
second laser pulse via a plasma mirror and by controlling the electron beam focusing via
active plasma lenses. Here a more compact and efficient scheme is proposed to realize
simultaneous coupling of the electron beam and the laser pulse to the second stage with
plasma channels [1]. A special designed bending channel is used to guide a fresh laser into a
following straight channel, while the electron beam always propagate in the straight channel.
Benefiting from the shorter coupling distance and continuous guiding of the electron beam in
plasma, its transverse dispersion is suppressed. With moderate laser parameters, our
particle-in-cell simulations demonstrate that the electron beam from the previous
acceleration stage can be efficiently injected into the following stage for further acceleration,
where the re-injection ratio, stability, and beam quality can be kept at a high level.
At the same time, based on plasma channel, we propose a new scheme of controlled
X-ray radiation [2,3]. The laser centroid motion in a plasma channel can be well controlled
by tuning the channel depth and width. Wakefield behind the driver laser makes similar
transverse oscillation, which makes the electrons inside the wake structure do transverse
betatron motion and radiate. Three-dimensional PIC simulation and VDSR radiation
calculation codes are used to study plasma channel based Helical plasma undulator radiation.
It shows both the radiation spectrum and polarization can be well controlled.
[1] J. Luo, et al., submitted.
[2] M. Chen, et al., Light: Science & Applications 5, e16015 (2016).
[3] J. Luo, et al., Sci. Rep. 6, 29101 (2016)
