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arXiv · 1802.01926

Ionization injection in a laser wakefield accelerator subject to a transverse magnetic field

Q. Zhao·S. M. Weng·Z. M. Sheng·M. Chen·G. B. Zhang·W. B. Mori·B. Hidding·D. A. Jaroszynski·J. Zhang
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Abstract

The effect of an external transverse magnetic field on ionization injection of electrons in a laser wakefield accelerator (LWFA) is investigated by theoretical analysis and particle-in-cell simulations. On application of a few tens of Tesla magnetic field, both the electron trapping condition and the wakefield structure changes significantly such that injection occurs over a shorter distance and at an enhanced rate. Furthermore, beam loading is compensated for, as a result of the intrinsic trapezoidal-shaped longitudinal charge density profile of injected electrons. The nonlinear ionization injection and consequent compensation of beam loading lead to a reduction in the energy spread and an enhancement of both the charge and final peak energy of the electron beam from a LWFA immersed in the magnetic field.

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Q. Zhao, S. M. Weng, Z. M. Sheng, M. Chen, G. B. Zhang, W. B. Mori, B. Hidding, D. A. Jaroszynski, J. Zhang. 2018-02-06. Ionization injection in a laser wakefield accelerator subject to a transverse magnetic field. https://doi.org/10.1088/1367-2630/aac926

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