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Experimental demonstration of a tomographic five-dimensional phase-space reconstruction

S. Jaster-Merz1,*, R. W. Assmann1,†, J. Beinortaitė1, J. Björklund Svensson1,‡, R. Brinkmann1, F. Burkart1, P. Craievich2, H. Dinter1, P. González Caminal1,§ et al.

W. Hillert3, A. L. Kanekar1, M. Kellermeier1, W. Kuropka1, F. Mayet1, J. Osterhoff1,∥, B. Stacey1, M. Stanitzki1, T. Vinatier1, S. Wesch1, and R. D’Arcy1,¶

  • *Contact author: sonja.jaster-merz@desy.de
  • †Present address: GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany.
  • ‡Present address: Lund University, Lund, Sweden.
  • §Present address: ATG Science & Technology S.L., Barcelona, Spain.
  • ∥Present address: Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
  • Present address: Oxford University, Oxford, United Kingdom.
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Phys. Rev. Research 7, 043211 – Published 24 November, 2025

DOI: https://doi.org/10.1103/m4wh-mhdm

Abstract

Detailed knowledge of particle-beam properties is of great importance to understand and push the performance of existing and next-generation particle accelerators. We recently proposed a phase-space tomography method to reconstruct the five-dimensional (5D) phase space, i.e., the charge density distribution in all three spatial directions and the two transverse momenta. Here, we present the first experimental demonstration of the method at the FLASHForward facility at DESY. This includes the reconstruction of the 5D phase-space distribution of a GeV-class electron bunch, the use of this measured phase space to create a particle distribution for simulations, and the extraction of the transverse 4D slice emittance.

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Phys. Rev. Research 7, 043211– Published 24 November, 2025
  • Received 20 May 2025
  • Accepted 14 October 2025
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