A Gated Micro-Pulse Electron Gun

50483-98-I A Gated Micro-Pulse Electron Gun--FM Technologies, Inc., 10529-B Braddock Road, Fairfax, VA 22032-2236; (703) 425-5111 Dr. Frederick Mako, Principal Investigator Dr. Frederick Mako, Business Official DOE Grant No. DE-FG02-98ER82581 Amount: $75,000 Many applications in high energy physics and elsewhere require a large number (tens to thousands) of high-charge, short-duration electron bunches. Photocathodes are limited to a few pulses and are constrained by materials that suffer from performance, reliability, and robustness issues. They also require expensive high-power lasers, are restricted in repetition rate, and require complicated timing circuitry. This project will develop a new device called the gated micro-pulse gun which is not pulse-limited. A point design, verified by simulations, has demonstrated 50 to 100 electron bunches of 40 nano-coulombs of charge, a micro-pulse duration of 15-20 picoseconds, a normalized transverse emittance of about 20 millimeters-milliradians, and a particle energy of 0.1 million electron volts. Phase I is aimed at a detailed analysis to develop the gating concept and determine the key requirements. Preliminary work suggests that the device will have a fast switching time and should be capable of producing high-current densities and short micro-pulses at nominally 2% of the radio-frequency period. Commercial Applications and Other Benefits as described by the awardee: This electron gun should provide a high-charge, low-emittance, picosecond-long electron source suitable for many applications. Of particular applicability are klystrons, medical and industrial radio-frequency linacs, linear accelerators, wakefield accelerators, and accelerator test facilities. _