20 kW CW L Band Klystron for Driving Superconductor Accelerator Cavities

70186S02-II A >13 kW CW klystron is required for driving the Jefferson Laboratory (JLAB) Accelerator upgrade. The klystron must operate at high efficiency, even when the drive power is reduced by 30% from the nominal maximum, without changing the cathode voltage. This project will develop a klystron with a modulating anode that will allow the beam perveance to change rapidly, in order to track changes in the radio frequency drive power. In Phase I, feasibility was shown via computer modeling and a detailed design. A saturated power of 19 kW was achieved with an efficiency of 59%. All other requirements were met, including the ability to run at reduced power with high efficiency by use of a modulating anode. In Phase II, detailed mechanical designs will be completed, and the klystron will be fabricated, tested, and delivered. Commercial Applications and Other Benefits as described by awardee: The principal application will be as an accelerator driver. JLAB will require 150 klystrons. Other accelerators, including ones used in medical treatment systems, may also benefit from the development.