DiagNostic for Charging PheNomena

Dielectric materials are ubiquitous in accelerator structures for discovery science, industrial and medical applications. Further use of dielectrics in advanced accelerators, such as the dielectric wake field accelerator, also promises improved performance and cost savings. But undesirable electrical charging and/or damage of the dielectrics sometimes impedes performance, indicating that systematic study of charging is needed so as to select suitable dielectrics and to develop means to avert charging and damage. A diagnostic method is to be developed for detection of charging of dielectrics arising from a proximate electron beam. This diagnostic should also be capable of detecting damagebe it temporary or permanentthat can alter the dielectric properties and thus degrade the performance of the accelerator that embodies the dielectric element. A microwave cavity resonator is to be developed to enclose sample dielectric tubes through which an energetic electron beam can propagate. The cavity will be designed to detune and damp when charging of and/or damage to the dielectric occurs. Tests will be carried out for a variety of dielectrics, to provide understanding and guidance for selection of appropriate dielectrics for particular accelerator applications. Commercial Applications and Other Benefits: Advance knowledge of dielectric charging and damage that can occur in an accelerator can help designers select the appropriate material, without need for long and costly testing. Industrial accelerator designers can also benefit from this knowledge. Microwave test kits may be built and sold to accelerator designers, but would be a highly limited market. Thus, as with many R & amp;D projects in accelerator science, the commercial benefits will mostly be indirect.