We present preliminary testing results for single-cell accelerating structures intended for
high-gradient testing at 110 GHz. The purpose of this work is to study the basic physics of
ultrahigh vacuum RF breakdown in high-gradient RF accelerators. The accelerating
structures consist of π-mode standing-wave cavities fed with the TM01 circular waveguide
mode. We fabricated two structures one in copper and the other in CuAg alloy. Cold RF tests
with quasi-optical excitation confirm the design RF performance of the structures. The …

Toward High-Power High-Gradient Testing of mm-Wave Standing-Wave Accelerating
Structures … • mm-Wave/THz accelerating structures have shown the promise of high
gradient achieving GV/m fields • Understanding the performance of structures at highfrequency
and high-field is needed for adoption • Advanced manufacturing techniques deliver
expected RF performance for mm-Wave/THz accelerating structures • Quasi-optical
coupling and transport demonstrated • Integration with MW source now underway …