Development of High Power RF Windows and Waveguide Components For the Next Linear Collider

158 Development of High Power RF Windows and Waveguide Components For the Next Linear Collider--Calabazas Creek Research, 20937 Comer Drive, Saratoga, CA 95070-3753; (408) 741-8680 Dr. R. Lawrence Ives, Principal Investigator Dr. R. Lawrence Ives, Business Official DOE Grant No. DE-FG03-97ER82343 Amount: $75,000 Researchers at the Department of Energy¿s Stanford Linear Accelerator Center (SLAC) are developing high power sources and waveguide systems for the proposed advanced high energy physics experiment called the Next Linear Collider (NLC), which will require approximately 4,500 power sources called klystrons. While considerable success has been achieved, problems are beginning to occur with the reliability and robustness of waveguide components when subjected to the power levels and pulse widths required for the accelerator. While the current window design is working well at 50 MW, there is the possibility that new materials may provide increased power transmission capability, better quality control, and less expensive manufacture and assembly. This project will investigate the design of waveguide components using both advanced overmoded waveguide techniques and several new, advanced computational tools. In addition, the characteristics and opportunities offered by single-crystal sapphire and chemical vapor-deposited (CVD) diamond will be investigated. Successful development of these components could substantially reduce the number of power sources needed and the cost of each klystron. Phase I of this project will include the development of computer models of key components; the investigation of the applicability of single-crystal sapphires and CVD diamonds for the critical window component; and the preliminary design of a prototype window. Alternative waveguide concepts will also be studied and a preliminary design of a waveguide system will be prepared. In Phase II the design, manufacture, and test of a waveguide system transmitting 100 MW of power will be undertaken. Commercial Applications and Other Benefits as described by the awardee: Should the program succeed in developing waveguide components and windows capable of transmitting 100 MW of RF power, a serious problem with the current NLC waveguide system will be solved. The accelerator program will require thousands of these components which represents a major commercial opportunity. It will also facilitate a reduction in total system cost by reducing the number of klystrons required if higher power sources can be developed._