Recent advances in high power microwave electron accelerators for physics research

Abstract

Abstract There have been some large steps forward in the microwave electron linear accelerator art. More power, precision and versatility than heretofore are now available for use in the search for further fundamental knowledge in nuclear structure. A number of very high current linear accelerators of great precision are described, among which are the following 1. a 10-MeV synchrotron injector having 200 mA of pulse current with an energy spread of 1% and a divergence of less than 1 milliradian; 2. a 35-MeV with pulse currents up to 500 mA and 30 microsecond pulse length offering 2 × 10 12 neutrons per pulse ; 3. a very new 130-MeV linear accelerator for the U.S. National Bureau of Standards. A breakthrough in the problem of “beam blow-up” and its possible origin in TM 110 mode excitation is described. New accelerating structures have been employed to advantage in the elimination of this problem. A new and potentially useful R.F. power tube called the Amplitron is just emerging, and its attractive features are described. Techniques are now available for microwave linear accelerators of arbitrarily great precision and power output.