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arXiv · 2306.16945

Coherent radiation of an electron bunch colliding with an intense laser pulse

Evgeny Gelfer·Alexander Fedotov·Ondrej Klimo·Stefan Weber
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Abstract

We study the conditions for coherent radiation of an electron bunch driven by a counterpropagating strong pulsed electromagnetic plane wave. We derive the spectrum of the coherent radiation and show that it is emitted backwards with respect to the laser propagation direction and has a very narrow angular spread. We demonstrate that for a solid density plasma coherent radiation extends to frequencies up to hundreds of keV thereby enhancing the low-frequency part of the spectrum by many orders of magnitude. Our analytical findings are tested with 3D particle-in-cell simulations of an electron bunch passing through a laser pulse, clearly demonstrating how the coherence can essentially modify the observed radiation spectrum.

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Evgeny Gelfer, Alexander Fedotov, Ondrej Klimo, Stefan Weber. 2023-06-29. Coherent radiation of an electron bunch colliding with an intense laser pulse. https://arxiv.org/abs/2306.16945

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