High Efficiency Klystrons for Accelerator Applications

Klystrons are the most commonly used RF sources for high energy accelerators. Their efficiency significantly impacts the acquisition and operating cost of accelerator systems. Higher efficiency RF sources are required to reduce the cost for future accelerators and colliders. Calabazas Creek Research Inc., in collaboration with SLAC National Accelerator Laboratory, is developing a method for optimizing klystron efficiency and applying it to the design of a high-power klystron for a DOE-relevant accelerator project. The research includes the development of codes using a combination of synthesis and simulation, coupled with advance optimization techniques. Computational designs were achieved with efficiencies exceeding 85%. The program investigated two approaches predicted to achieve high efficiency and evaluated trade-offs between the approaches. A design was selected that achieves efficiency exceeding 85% with the simplest circuit configuration. The klystron design will be optimized using several design codes to verify the computational performance. The optimum design will be used to generate the mechanical design, and a prototype klystron will be built and tested at high power. Commercial Applications and Other BenefitsKlystrons are used in many applications, including medical and industrial accelerators, radar, communication, and defense systems. Increased efficiency will result in less expensive devices by reducing fabrication as well as reducing power supply and operating costs.