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Coaxial integrated linear accelerator powered by a high-efficiency and high-power transit-time oscillator

Zi-Jing Zhang1, Weihao Liu2,*, and Hongliang Xu1,†

  • *Contact author: liuwhao@nuaa.edu.cn
  • †Contact author: hlxu@ustc.edu.cn
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Phys. Rev. Accel. Beams 29, 021301 – Published 5 February, 2026

DOI: https://doi.org/10.1103/dck2-79z4

Abstract

Integrating a high-power microwave source with an accelerating structure into a single device is a key strategy for developing compact, even portable, high-energy particle accelerators, which hold significant promise for scientific, medical, and industrial applications. To achieve this objective, we propose integrating an X-band coaxial transit-time oscillator (CTTO) microwave source with an X-band accelerating structure, thereby drastically minimizing the total volume of particle accelerators. Leveraging the CTTO’s advantages, low operating voltage, stable frequency, high power, and high efficiency, along with the high acceleration gradient of X-band accelerators, our design demonstrates that a CTTO operating at 50 kV (generating 7.8 MW of radio-frequency power at 9.3 GHz) can accelerate an electron beam from 50 keV to 10.96 MeV over a 320 mm length.

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Phys. Rev. Accel. Beams 29, 021301– Published 5 February, 2026
  • Received 25 August 2025
  • Accepted 14 January 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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