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Title Input RF Coupler Windows for RIA Cavities
Type Poster coupler / tuner / controls
Abstract The RF coupler window was designed by AMAC and MSU to meet the specification requirements for the proposed RIA accelerator project. CPI performed the manufacturing optimization and fabrication. The preparation, testing, and conditioning were performed at the Jefferson Laboratory and the results are presented in another paper at this conference.The main specification parameters for RIA prototype coupler are: VSWR: 1.05 or lower at 805 MHz; Maximum CW power: 10 kW; External Q of coupler: 2 x 107; Maximum thermal load to 2 K circuit: 2 W; Operating pressure: <5 x 10-9 torr; Radiation resistance: 4 x 108 rads. Air-cooling removes the dissipated power at the window and the antenna and outer conductor are conduction cooled.  The outer conductor is copper plated stainless with a 50 or 77 K thermal intercept. The RIA cryostat geometry requires a coaxial 805 MHz coupler design with a transition to standard 3-1/8 in. transmission line. This coupler design is similar to the AMAC SNS high power prototype couplers. The geometry incorporates chokes at the inner and outer conductor. CPI fabricated two coupler window assemblies. The coupler windows have been conditioned and successfully RF tested at the Jefferson Laboratory, and meet or exceeds the RIA specifications with small temperature increases in the ceramic and no arcing. Calculation results, details, drawings, and a summary of the RF tests results for this coupler window will be presented in this paper.

List of authors...

Principle author first.

Last (Family) Name First Name (Initials only) Affiliation or Organization (abbreviations if possible)
Shu Quan-Sheng AMAC
Susta Joe AMAC
Cheng Guangfeng AMAC
Grimm Terry NSCL
Popielarski John NSCL
Einarson Steven CPI
Treado Todd CPI



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