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  • Open Access

Wide frequency-range acceleration using second-harmonic rf buckets in fixed-field accelerators

T. Uesugi*, Y. Ishi, and Y. Mori

  • Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494 Japan

  • *Contact author: uesugi.tomonori.2n@kyoto-u.ac.jp
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Phys. Rev. Accel. Beams 29, 031303 – Published 27 March, 2026

DOI: https://doi.org/10.1103/nch5-p3rk

Abstract

We propose a novel acceleration scheme for fixed-field accelerators (FFAs), in which rf buckets with harmonic numbers h=1 and h=2 are time-sequenced to form a single, continuous acceleration path. This approach completes acceleration in two rf frequency sweeps, thereby reducing the total frequency sweep range and shortening the repetition period. The feasibility of this method is demonstrated through longitudinal simulations based on parameters of the FFA at the Institute for Integrated Radiation and Nuclear Science, Kyoto University (KURNS). We also establish operational conditions under which the second-harmonic rf bucket remains stable and practically usable.

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Phys. Rev. Accel. Beams 29, 031303– Published 27 March, 2026
  • Received 12 November 2025
  • Accepted 3 March 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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