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Coherent Ionization of Atoms by Dense Beams of Extreme Relativistic Electrons

S. Kim, C. Müller, and A. B. Voitkiv

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Phys. Rev. Lett. 136, 213202 – Published 27 May, 2026

DOI: https://doi.org/10.1103/knz2-4fw4

Abstract

Ionization is one of the basic physical processes, occurring when charged particles penetrate atomic matter. Here, we predict a novel ionization mechanism, arising in collisions with very dense and compact beams of extreme relativistic electrons, in which a significant fraction of the beam electrons acts coherently as a single “superprojectile.” We compare this mechanism with the tunnel and overbarrier ionization and ionization by individual electrons, demonstrating that it can strongly dominate the ionization process. We also show that this mechanism and the tunnel ionization are very sensitive to the spatiotemporal structure of the beam that can be used for analyzing the beam properties.

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Phys. Rev. Lett. 136, 213202– Published 27 May, 2026
  • Received 25 August 2025
  • Revised 9 January 2026
  • Accepted 30 April 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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