Development of a Diamond-Based Cylindrical Dielectric Loaded Accelerating Structure

High energy particle accelerator structures based on dielectric tubes are presently being studied as a promising technology for next generation linear colliders. This project will develop a diamond-based accelerating structure that can sustain an accelerating gradient larger than 600 MV/m, significantly in excess of the limits experimentally tested for conventional accelerating structures. In Phase I, a cylindrical diamond-based DLA structure was designed. Using a plasma CVD process, very high quality diamond tubes (5.5 mm diameter, thickness ~ 0.5 mm, and 2.5 cm long) were fabricated. Surface quality was established using electron microscopy, and the electronic parameters of the diamond were measured using micro Raman and micro-photoluminescence spectroscopy. Phase II will complete the CVD fabrication of the diamond tubes needed to build a full-size K-band prototype accelerator structure. Numerical studies will be conducted to optimize the accelerating structure parameters. Wakefield acceleration experiments using the diamond structure will be performed at the Wakefield Accelerator Facility at Argonne National Laboratory. Commercial Applications and other Benefits as described by the awardee: The diamond tubes should be applicable to the development of high-efficiency next-generation accelerators and to cylindrical diamond components for high-voltage and microwave applications. These diamond tubes also could be used for molecular filters, drilling tools, waveguides, and hypodermic needles