C. ADOLPHSEN, C. NANTISTA (SLAC)
The linacs of the NLC will contain several thousand X-Band accelerator structures operating at an unloaded gradient of 72 MV/m. A major concern is the damage that can occur in these structures from rf breakdown. Experimentally, pitting has been observed on the surfaces of the cell irises in prototype structures that have been processed to high gradients. To better understand this damage, one would like to model the structure operation during rf breakdown. However, this very difficult to do at a microscopic level. Instead, we have modeled the macroscopic characteristics of breakdown, in particular, we use an equivalent circuit of the structure where a time dependent cell Q is introduced to match the general characteristics of the observed forward and reflected rf pulses during breakdown. In this paper, we describe these results and discuss their implications for designing high gradient structures.
* Work supported by Department of Energy contract DE-AC03-76SF00515
Comments or Questions to