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arXiv · 1703.09053

Sustained electron self-injection in an evolving ellipsoid bubble for laser-plasma interaction

X. F. Li·Q. Kong·S. Kawata·Y. J. Gu·Q. Yu·J. F. Qu
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Abstract

Electron injection in an evolving ellipsoid bubble for laser wakefield acceleration is investigated by 2.5D PIC (Particle-In-Cell) simulation. Generally speaking, the self-injection electrons come from the position near the transverse radius in the bubble acceleration. However, we found the electrons near the laser axis also can be trapped into a longitudinal-expanding bubble. Moreover, this new self-injection mechanism is still existence after the electron self-injection stopped, which initially locates at near the bubble transverse radius. This phenomenon is confirmed through single-particle dynamic simulation. Besides, this new mechanism brings a high charge electron beam for acceleration, due to the sustained self-injection.

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X. F. Li, Q. Kong, S. Kawata, Y. J. Gu, Q. Yu, J. F. Qu. 2017-03-27. Sustained electron self-injection in an evolving ellipsoid bubble for laser-plasma interaction. https://arxiv.org/abs/1703.09053

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