High Gradient Test of a Standing Wave Dielectric Loaded Accelerating Structure

Dielectric based accelerators have potentials to provide a low cost, ultra-high gradient, high energy collider design, but, due to the available rf power limitations in the available test facilities and some design issues in the past, they have not yet been tested to date under high gradient conditions. We will develop and conduct high gradient rf tests of a Standing Wave (SW) Dielectric Loaded Accelerating (DLA) structure, which allows high gradient ( & gt 100 MV/m) tests with a usage of & lt;10 MW input rf power. The structure is planned to be tested at the Naval Research Laboratory, where it can be operated at gradients as high as 170 MV/m with 20 MW rf power from the X-band Magnicon. In Phase I of this project, an X-band standing wave DLA structure will be designed, fabricated, and bench tested in preparation for a high power rf test at NRL. Commercial Applications and Other Benefits: This rf breakdown study using a standing wave DLA structure will very likely lead to demonstration of an accelerating gradient as high as 170 MV/m which may lead toward the design of a future high energy collider. Alternatively, this experiment could provide the first hard evidence of rf breakdown limits of dielectric based accelerators which provides useful experimental data for the global effort to understand the breakdown mechanism