• K. Yokoyama, S. Fukuda, Y. Higashi, T. Higo, N. Kudoh, S. Matsumoto, Y. Watanabe
  KEK, Ibaraki

High-gradient RF breakdown studies have been in progress at Nextef (New X-band Test Facility at KEK) since 2006. To study the characteristics of different materials on high-field RF breakdown, we have performed high-gradient experiments by using narrow waveguides that has a field of around 140 MV/m at 50 MW power. Breakdown rates of stainless-steel and copper cases were measured and the results are described in this paper.