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arXiv · 2608.25020

High-charge collimated and energy-selected laser-driven MeV electron beams produced by magnetic selection

I. Cohen·I. Slabu·Q. Peysson·S. Dorard·Y. Abe·J. Béard·T. Moraine·S. N. Chen·A. Chessa·K. Iida·P. Kempski·Y. Kuramitsu·H. Kusano·F. Nikaido·M. Ruszkowski·K. Sakai·N. Tamaki·O. Tesileanu·J. Fuchs
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Abstract

We have developed a compact passive energy-selector for MeV-range electrons produced by irradiating solid targets by ultra-intense short-pulse lasers. The device allows for generating electron beams with a variable energy spread over a broad range of energies, from tens of keV to tens of MeV. Here we have demonstrated its use by producing electrons from solid targets in the MeV range and with a ~10% bandwidth, thereby compensating the intrinsic broadband nature of the electrons produced from such source. Coupled with a pulsed magnetic field to further compensate the intrinsic large divergence of this source, it allows to produce a highly-collimated beam of narrow-band and ultra-fast electrons, suitable for a wide range of applications, e.g. radiation therapy or time-resolved electron probing.

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I. Cohen, I. Slabu, Q. Peysson, S. Dorard, Y. Abe, J. Béard, T. Moraine, S. N. Chen, A. Chessa, K. Iida, P. Kempski, Y. Kuramitsu, H. Kusano, F. Nikaido, M. Ruszkowski, K. Sakai, N. Tamaki, O. Tesileanu, J. Fuchs. 2026-08-25. High-charge collimated and energy-selected laser-driven MeV electron beams produced by magnetic selection. https://arxiv.org/abs/2608.25020

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