Plasma-wakefield acceleration of a positron beam.
Plasma-wakefield excitation by positron beams is examined in a regime for which the plasma dynamics are highly nonlinear. Three dimensional particle-in-cell simulations and physical models are presented. In the nonlinear wake regime known as the blowout regime for electrons, positron wakes exhibit an analogous "suck-in" behavior. Although analogous, the two wakefield cases are quite different in terms of their amplitudes, wavelengths, waveforms, transverse profiles, and plasma density dependence. In a homogenous plasma, nonlinear positron wakes are smaller than those of the corresponding electron case. However, hollow channels are shown to enhance the amplitude of the positron wakes.
Lee
S
S
University of Southern California, Los Angeles, California 90089, USA.
Katsouleas
T
T
Hemker
R G
RG
Dodd
E S
ES
Mori
W B
WB