Efficient 800-MHz Two-Stage Multi-Beam Klystron

Energy consumption is one of the major concerns when planning large-scale high energy accelerator projects such as the Future Circular Collider (FCC-ee) and similar accelerators. Efforts to reduce overall installation and operational costs of high radio frequency (RF) power sources for planned large-scale accelerators are focused among other things on maximizing the efficiency of the RF sources when reducing their manufacturing costs. In this approach, a primary candidate is an 800 MHz RF source with a power output of ~1.5 MW and high duty factor. A new concept of the Two-Stage Multi Beam Klystron (TS-MBK) that allows for a remarkably high RF power production efficiency (the preliminary result is 82%) is proposed. It also yields a compact design and delivers a cost-effective electro- mechanical solution. The design is for an 800 MHz, 1.5 MW peak-power klystron. The high efficiency is predicted that is about 15-20% higher than conventional MBK designs, and is due to good bunching of its twelve, 10-kV, 12-A 2.5 μP beamlets; followed by 50 kV post-acceleration that results in 0.17 μP beamlets that drive the output cavity. During Phase I of this project, Omega-P R&D, Inc will refine its conceptual design of the 800 MHz TS-MBK, perform mechanical tolerance analysis, and produce the device design. In parallel, Communication & Power Industries, LLC will perform preliminary engineering design, cost estimates for fabrication and testing of a prototype to be carried out during Phase II, and preliminary market research. The proposed RF source is for use in accelerator, medical, national security, and environmental cleanup applications. The 800 MHz frequency for this project is chosen to match potential future needs of the Future Circular Collider (FCC) and similar large accelerators.