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  • Letter
  • Open Access

Proof-of-principle experiment of a beam extraction over millions of turns using stable resonance islands and bent crystal

D. E. Veres*, P. Arrutia, S. Cettour Cave, B. H. F. Lindström†, M. Giovannozzi‡, L. E. Pauwels§, F. F. Van der Veken, and F. M. Velotti

G. Franchetti∥

  • CERN, Esplanade des Particules 1, 1121 Meyrin, Switzerland

  • *Also at Goethe University, 60323 Frankfurt am Main, Germany.
  • †Also at John Adams Institute at Royal Holloway, University of London, Egham, United Kingdom.
  • ‡Contact author: massimo.giovannozzi@cern.ch
  • §Also at Université Libre de Bruxelles, Avenue F. D. Roosevelt 50, B-1050 Brussels, Belgium.
  • ∥Also at Goethe University Frankfurt, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany and Helmholtz Forschungsakademie Hessen für FAIR (HFHF), GSI Helmholtzzentrum für Schwerionenforschung, Campus Frankfurt, Frankfurt am Main, Germany.
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Phys. Rev. Research 8, L022055 – Published 22 June, 2026

DOI: https://doi.org/10.1103/n93z-3ry8

Abstract

A recent study, D. E. Veres et al. [Phys. Rev. Res. 6, L042018 (2024)], has introduced an advanced method aimed at extracting from a circular particle accelerator over millions of turns using stable islands and a bent crystal. This technique leverages the strength of nonlinear beam dynamics along with adiabatic trapping and transport within stable islands, in combination with a bent silicon crystal, to provide an efficient extraction of hadron beams over millions of turns. The positive and encouraging results of the comprehensive numerical simulations were validated through a successful proof-of-principle experiment at the CERN Super Proton Synchrotron, which demonstrated the feasibility of the technique. This Letter presents a detailed discussion and analysis of the experimental results.

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Phys. Rev. Research 8, L022055– Published 22 June, 2026
  • Received 25 February 2026
  • Accepted 3 May 2026
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