Development of a 1 MW CW 704 MHz Elliptic Beam Klystron for Nuclear Physics Accelerators

High efficiency radio frequency (RF) power sources are needed in the frequency range 300-1500 MHz because they are essential for the operation of high-power particle accelerators for nuclear physics research. Applications include the Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson National Accelerator Laboratory (JLab), the Relativistic Heavy Ion Collider (RHIC) and Electron-Ion Collider (eRHIC) at Brookhaven National Laboratory (BNL), the Rare Isotope Accelerator (RIA) at Argonne National Laboratory (ANL), and the Spallation Neutron Source (SNS) at Efficienct Oak Ridge National Laboratory (ORNL). At present, conventional circular-beam klystrons are the technology of choice for high-power accelerators. However, they are not efficient when operating at high-power and low beam voltages, conditions that are required for continuous-wave (CW) high-power. This project will develop an innovative elliptic beam klystron, using proprietary elliptic electron beam technology, which will meet the requirement for a 1 MW cw RF power source at 704 MHz. An efficiency of 75% is possible with the elliptic beam interaction. Commercial Applications and other Benefits as described by the awardee: An elliptic beam klystron not only would be a significant technical achievement, but also would replace conventional klystrons in the commercial marketplace, which has annual sales of $200M worldwide.