X-Band Bunched Electron Injector

The development of high-current, short-duration pulses of electrons has been a challenging problem for many years. High current pulses are widely used in injector systems for electron accelerators, both for industrial linacs as well as high-energy accelerators for linear colliders. Short-duration pulses are also used for microwave generation in klystrons and related devices, for injectors to perform research on advanced methods of particle acceleration, and for injectors used as free-electron-laser (FEL) drivers. The proposed method to be described below is promising because of a natural bunching process which self-synchronizes to the rf, thus eliminating the need for pre-buncher section(s), timing system, and lasers. Also, the repetition rate can be orders of magnitude greater. FM Technologies proposes a novel high current, picosecond X-band bunched electron gun system which is named the X-band Bunched Electron Injector (XBEI). The heart of the XBEI is a self-bunching electron gun, the X-Band Micro-Pulse Gun (XMPG). By adding an external electron amplifier stage and high energy RF or pulsed voltage post acceleration, an inexpensive, simple, robust electron injector or klystron self-bunching electron gun would result. In Phase I, electron amplification with diamond in the XMPA has been demonstrated, and measurements of electron current gain, charge per bunch, rf power, beam power and other key parameters have been performed. Phase II will be aimed at design, fabrication, and testing of an XBEI to 5-6 MeV and a new type of klystron. This includes development of the electron amplifier for the XMPG and rf acceleration and a klystron output cavity. The experiments will be to establish the baseline for characterizing the XBEI device for suitability for a variety of potential applications. Commercial Applications and Other Benefits: If successful, this micro-pulse electron amplifier injector (XBEI) will provide a high power, low admittance, picosecond-long electron source which is suitable for many applications. Of particular interest are high energy picosecond electron injectors for linear colliders, free electron lasers, medical and industrial rf linacs, a high-frequency driver for rf sources