Novel Approaches for Attaining High Accelerating Fields in Superconducting Cavities

  • Q. S. Shu
  • J. Graber
  • W. Hartung
  • J. Kirchgessner
  • D. Moffat
  • R. Noer
  • H. Padamsee
  • D. Rubin
  • J. Sears
Part of the Applications of Cryogenic Technology book series (APCT, volume 10)

Abstract

Present-day superconducting (SC) radio-frequency (rf) cavity structures used in particle accelerators provide accelerating fields (Eacc) up to 10 MV/m. Field emission is the most serious obstacle to reaching the higher fields called for in future applications. We have used heat treatment (up to 1500°C), along with high-power processing of cavities and temperature mapping, to suppress field emission and analyze emitter properties. In 27 fired cavities, we have raised the average Eacc to 26 MV/m from the 14 MV/m obtained with chemical treatment (CT) alone; the highest Eacc reached is 30 MV/m. Non-accelerating cavities have also been made to investigate the highest rf field SC Nb can support; 145 MV/m has been reached. A 6-cell cavity has been constructed in an effort to extend our achievements from single-cell test cavities toward the accelerating structures planned for TESLA (a TeV ee+ linear collider); preliminary measurements with CT only reached Eacc = 17 MV/m. The conceptual design of a B-factory cavity is also briefly discussed.

Keywords

Heat Treatment Particle Accelerator Cavity Field Field Enhancement Factor Surface Electric Field 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1991

Authors and Affiliations

  • Q. S. Shu
    • 1
  • J. Graber
    • 1
  • W. Hartung
    • 1
  • J. Kirchgessner
    • 1
  • D. Moffat
    • 1
  • R. Noer
    • 1
  • H. Padamsee
    • 1
  • D. Rubin
    • 1
  • J. Sears
    • 1
  1. 1.Laboratory of Nuclear StudiesCornell UniversityIthacaUSA

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