Enhancement of effective linear RF surface resistance of superconducting surfaces by microscopic topography

doi:10.1016/j.nima.2018.05.004

This content will become publicly available on May 21, 2019

Title: Enhancement of effective linear RF surface resistance of superconducting surfaces by microscopic topography

Article Details
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Minimization of Radio-Frequency (RF) dissipation on superconducting surfaces is of interest for many applications. A prominent one is the use of Superconducting RF (SRF) cavities for charged particle acceleration. In addition to our previous investigation which characterized the occurrence of high-field non-linear losses by microscopic surface topography, the topic of increased linear losses as a function of surface topographic character merits consideration. Surfaces with isotropic homogeneous surface topography may be well characterized by power spectral density (PSD) derived from systematic height measurements. PSD characterizations of representative niobium cavity surface treatments have been developed: Electro-Polishing (EP), Nano-Mechanical Polishing (NMP) and Centrifugal Barrel Polishing (CBP) A perturbation model based on PSD statistical analysis is used to calculate additional RF loss on these surfaces when superconducting. The model assesses the penetration depth effects for a superconductor. We thus estimate the RF power dissipation ratio between these rough surfaces and an ideal smooth surface.

Authors:

Xu, Chen ^[1] ; Reece, Charles E. ^[2] ; Kelley, Michael J. ^[3] ; Takacs, Peter ^[4]

Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); College of William and Mary, Williamsburg, VA (United States)
Brookhaven National Lab. (BNL), Upton, NY (United States)

Publication Date:: 2018-05-21

Report Number(s):: JLAB-ACC-17-2623; DOE/OR/23177-4308
Journal ID: ISSN 0168-9002; PII: S0168900218305898

Grant/Contract Number:: AC05-06OR23177

Type:: Accepted Manuscript

Journal Name:: Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment

Additional Journal Information:: Journal Volume: 904; Journal ID: ISSN 0168-9002

Publisher:: Elsevier

Research Org:: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

Sponsoring Org:: USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

OSTI Identifier:: 1458441


                    Xu, Chen, Reece, Charles E., Kelley, Michael J., and Takacs, Peter. Enhancement of effective linear RF surface resistance of superconducting surfaces by microscopic topography.  United States: N. p.,  
        Web.  doi:10.1016/j.nima.2018.05.004.

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                    Xu, Chen, Reece, Charles E., Kelley, Michael J., & Takacs, Peter. Enhancement of effective linear RF surface resistance of superconducting surfaces by microscopic topography.  United States.  doi:10.1016/j.nima.2018.05.004.

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                    Xu, Chen, Reece, Charles E., Kelley, Michael J., and Takacs, Peter. 2018.  
        "Enhancement of effective linear RF surface resistance of superconducting surfaces by microscopic topography".  United States.  
        doi:10.1016/j.nima.2018.05.004.

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@article{osti_1458441,

  title        = {Enhancement of effective linear RF surface resistance of superconducting surfaces by microscopic topography},

  author       = {Xu, Chen and Reece, Charles E. and Kelley, Michael J. and Takacs, Peter},

  abstractNote = {Minimization of Radio-Frequency (RF) dissipation on superconducting surfaces is of interest for many applications. A prominent one is the use of Superconducting RF (SRF) cavities for charged particle acceleration. In addition to our previous investigation which characterized the occurrence of high-field non-linear losses by microscopic surface topography, the topic of increased linear losses as a function of surface topographic character merits consideration. Surfaces with isotropic homogeneous surface topography may be well characterized by power spectral density (PSD) derived from systematic height measurements. PSD characterizations of representative niobium cavity surface treatments have been developed: Electro-Polishing (EP), Nano-Mechanical Polishing (NMP) and Centrifugal Barrel Polishing (CBP) A perturbation model based on PSD statistical analysis is used to calculate additional RF loss on these surfaces when superconducting. The model assesses the penetration depth effects for a superconductor. We thus estimate the RF power dissipation ratio between these rough surfaces and an ideal smooth surface.},

  doi          = {10.1016/j.nima.2018.05.004},

  journal      = {Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment},

  number       = ,

  volume       = 904,

  place        = {United States},

  year         = {2018},

  month        = {5}

}

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Free Publicly Accessible Full Text
This content will become publicly available on May 21, 2019
Publisher's Version of Record
10.1016/j.nima.2018.05.004
https://doi.org/10.1016/j.nima.2018.05.004

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Title: Enhancement of effective linear RF surface resistance of superconducting surfaces by microscopic topography

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