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324-MHz interdigital H-mode drift tube linac for muon acceleration

Y. Nakazawa1,*, Y. Ibaraki2,†, E. Cicek1, K. Futatsukawa1, Y. Fuwa3, N. Hayashizaki4, T. Iijima2,5, H. Iinuma6, Y. Iwata7 et al.

Y. Kondo3,6, T. Mibe1, S. Mizobata1, T. Morishita3, M. Otani1, K. Sumi1, and Y. Takeuchi2

  • *Contact author: yuga.nakazawa@kek.jp
  • †Contact author: yuka.ibaraki122602@gmail.com
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Phys. Rev. Accel. Beams 29, 093201 – Published 1 September, 2026

DOI: https://doi.org/10.1103/1l3t-rvmf

Abstract

We have constructed a 324-MHz interdigital H-mode drift tube linear accelerator (IH-DTL) with an alternating phase focusing method. This IH-DTL will be part of a muon linear accelerator (linac) being developed at the Japan Proton Accelerator Research Complex for a precise measurement of the muon anomalous magnetic moment and a search for the muon electric dipole moment. The IH-DTL is 1.45  m long and accelerates muons from β=v/c=0.08 to 0.28. Low-power tuning was performed using six slug tuners, which reduced the peak-to-peak on-axis field error to 1.4%. Following 94 h of high-power conditioning, the IH-DTL demonstrated stable operation at the nominal peak power of 390  kW and a duty factor of 0.1%, corresponding to the designed accelerating field (E0) of 3.6  MV/m. This paper presents the construction, low-power rf tuning, and high-power performance of the 324-MHz IH-DTL.

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Phys. Rev. Accel. Beams 29, 093201– Published 1 September, 2026
  • Received 22 June 2026
  • Accepted 4 August 2026
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