Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

High gradient RF breakdown study

Conference ·
OSTI ID:346921
;  [1]; ; ; ;  [2]
  1. Univ. of California, Davis, CA (United States)
  2. Stanford Linear Accelerator Center, CA (United States)
Stanford Linear Accelerator Center and UC Davis have been investigating high gradient RF breakdown and its effects on pulse shortening in high energy microwave devices. RF breakdown is a critical issue in the development of high power microwave sources and next generation linear accelerators since it limits the output power of microwave sources and the accelerating gradient of linacs. The motivation of this research is to find methods to increase the breakdown threshold level in X-band structures by reducing dark current. Emphasis is focused on improved materials, surface finish, and cleanliness. The test platform for this research is a traveling wave resonant ring. A 30 MW klystron is employed to provide up to 300 MW of traveling wave power in the ring to trigger breakdown in the cavity. Five TM{sub 01} cavities have previously been tested, each with a different combination of surface polish and/or coating. The onset of breakdown was extended up to 250 MV/m with a TiN surface finish, as compared to 210 MV/m for uncoated OFE copper. Although the TiN coating was helpful in depressing the field emission, the lowest dark current was obtained with a 1 {micro}inch surface finish, single-point diamond-turned cavity.
OSTI ID:
346921
Report Number(s):
CONF-980601--
Country of Publication:
United States
Language:
English

Similar Records

RF breakdown studies in X-Band klystron cavities
Conference · Thu May 01 00:00:00 EDT 1997 · OSTI ID:489595

RF breakdown experiments at SLAC
Journal Article · Sat May 01 00:00:00 EDT 1999 · AIP Conference Proceedings · OSTI ID:704167

RF Tests of an 805 MHz Pillbox Cavity at Lab G of Fermilab
Conference · Thu May 01 00:00:00 EDT 2003 · OSTI ID:838444