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arXiv · 1606.02336

Wake excited in plasma by an ultra-relativistic point-like bunch

G. Stupakov·B. Breizman·V. Khudik·G. Shvets
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Abstract

A plasma flow behind a relativistic electron bunch propagating through a cold plasma is found assuming that the transverse and longitudinal dimensions of the bunch are small and the bunch can be treated as a point charge. In addition, the bunch charge is assumed small. A simplified system of equations for the plasma electrons is derived and it is shown that, through a simple rescaling of variables, the bunch charge can be eliminated from the equations. These equations have a unique solution, with an ion cavity formed behind the driver. The equations are solved numerically and the scaling of the cavity dimensions with the driver charge is obtained. A numerical solution for the case of a positively charged driver is also found.

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G. Stupakov, B. Breizman, V. Khudik, G. Shvets. 2016-06-07. Wake excited in plasma by an ultra-relativistic point-like bunch. https://doi.org/10.1103/physrevaccelbeams.19.101302

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