  X-band accelerator structures, meeting the Next Linear Collider (NLC) design
requirements, have been found to suffer damage due to radio frequency (RF)
breakdown when processed to high gradients. Improved understanding of these
breakdown events is desirable for the development of structure designs,
fabrication procedures, and processing techniques that minimize structure
damage. Using an array of acoustic sensors, we have been able to pinpoint the
location of individual breakdown events. However, a more accurate localization
is required to understand the interaction between the phonon or the sound wave
with the OFE copper.
