Bunch-excited wakefield in dielectric waveguide with hollow plasma channel

K. V. Galaydych; P. I. Markov; G. V. Sotnikov

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arXiv · 2311.17614

Bunch-excited wakefield in dielectric waveguide with hollow plasma channel

K. V. Galaydych·P. I. Markov·G. V. Sotnikov

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Abstract

Wakefield excitation by a single relativistic electron bunch in a plasma-dielectric accelerating structure has been studied both analytically and numerically. The structure represents a dielectric-loaded cylindrical metal waveguide, which has partially plasma-filled channel (the hollow plasma channel) to transport charged particles. Assuming the linear regime of excitation, analytical expressions have been derived for the longitudinal and radial wakefields generated by a finite-size electron bunch. Axial profiles of wakefield component amplitudes have been studied, and their mode and spectrum analyses have been performed. Furthermore, the electron bunch-driven wakefield excitation has been PIC-simulated numerically for the quasi-linear regime. The comparative analysis of the data resulting from analytical studies and the ones obtained by numerical simulation has demonstrated qualitative agreement between the results.

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K. V. Galaydych, P. I. Markov, G. V. Sotnikov. 2023-11-29. Bunch-excited wakefield in dielectric waveguide with hollow plasma channel. https://arxiv.org/abs/2311.17614

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