Dimensional analysis of high gradient RF cavity considering shrink-fit construction method

Aghayan, Mahdi; Masoudi, S. Farhad; Ghgasemi, Farshad; Shaker, Hamed

doi:10.22034/rpe.2021.302677.1038

Document Type : Research Article

Authors

¹ Department of Physics, K.N. Toosi University of Technology, P.O. Box 15875-4416, Tehran, Iran

² Physics and Particle Accelerators Research school, Nuclear Science and Technology Research Institute, Tehran, Iran

³ Canadian Light Source, Saskatoon, Canada

https://doi.org/10.22034/rpe.2021.302677.1038

Abstract

Advantage of non-brazing methods in manufacturing of cavities has been considered in high gradient studies because of the softening of copper by brazing cavities at high temperatures. Recent studies with hard copper cavities have been shown that the harder materials can reach larger accelerating gradients for the same breakdown rate. Shrinking, as a braze-free method for construction of the cavities, was used recently to fabricate and assemble acceleration cavities of an electron linear accelerator at the Institute for Research in Fundamental Science (IPM-Iran). Based on the results obtained in this project, this paper proposes the design of a 3-cell S-band standing wave structure operating at 2.9985 GHz for high gradient tests, considering shrink-fit construction method. The desired cavity consists of three cells so that the maximum gradient in the middle cell is about twice that of the surrounding cells. Simulation with Ansys-HFSS showed that maximum axial electric field 59 MV.m^-1 achievable for 2 MW input power in middle cell.

Highlights

• A shrink-fit method is proposed for the construction high-gradient S-band cavity.
• Radiofrequency design of a 3-cell high gradient S-band cavity was performed.
• maximum gradient in the middle cell is twice that of the adjacent cells.
• Simulations showed maximum axial electric field of 59 MV.m⁻¹ is achievable for 2 MW input power.
• The breakdown rate less than 10−6 bpp.m⁻¹ is accessible for pulse length up to 80 μs.

Keywords

20.1001.1.26456397.2021.2.3.4.8

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Radiation Physics and Engineering

Dimensional analysis of high gradient RF cavity considering shrink-fit construction method

References

References

Volume 2, Issue 3
September 2021
Pages 25-30

Dimensional analysis of high gradient RF cavity considering shrink-fit construction method

References

References

Volume 2, Issue 3September 2021Pages 25-30

Volume 2, Issue 3
September 2021
Pages 25-30