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High-efficiency klystrons from a dream to a reality

C. Marrelli*, N. Catalan Lasheras, P. Alonso Arias, O. Brunner, D. Soriano Guillen, I. Syratchev, and U. N. Zaib†

A. Baig‡ and G. Burt

K. Haj Khlifa and A. Beunas

T. Anno

J. Cai

  • CERN, Geneva, Switzerland

  • *Contact author: Chiara.Marrelli@cern.ch
  • †Also at School of Engineering, Lancaster University.
  • ‡Present address: Science and Technology Facilities Council (STFC).
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Phys. Rev. Accel. Beams 29, 103801 – Published 14 October, 2026

DOI: https://doi.org/10.1103/6bj3-grxp

Abstract

During the past decade, a comprehensive research and development (R&D) program on high-efficiency klystrons has been carried out in collaboration with industry. Initial prototypes have undergone testing, with experimental results showing significant promise. This paper is an extended and updated version of the work presented in Catalan-Lasheras et al. [JACoW IPAC2024, FRYD1 (2024)]. After a brief overview of the R&D program, it presents the latest experimental findings and discusses future developments, including novel vacuum tube topologies aimed at next-generation collider applications.

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Phys. Rev. Accel. Beams 29, 103801– Published 14 October, 2026
  • Received 14 April 2026
  • Accepted 11 September 2026
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