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Title: Ion dynamics driven by a strongly nonlinear plasma wake
Abstract In plasma wakefield accelerators, the wave excited in the plasma eventually breaks and leaves behind slowly changing fields and currents that perturb the ion density background. We study this process numerically using the example of a Facility for Advanced aCcelerator Experimental Tests (FACET) experiment where the wave is excited by an electron bunch in the bubble regime in a radially bounded plasma. Four physical effects underlie the dynamics of ions: (1) attraction of ions toward the axis by the fields of the driver and the wave, resulting in formation of a density peak, (2) generation of ion-acoustic solitons following the decay of the density peak, (3) positive plasma charging after wave breaking, leading to acceleration of some ions in the radial direction, and (4) plasma pinching by the current generated during the wave-breaking. The interplay of these effects results in the formation of various radial density profiles, which are difficult to produce in any other way.  more » « less
Award ID(s):
2010435
PAR ID:
10427956
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Plasma Physics and Controlled Fusion
Volume:
64
Issue:
4
ISSN:
0741-3335
Page Range / eLocation ID:
045003
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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