Carbon Nano-Tube (CNT) cathodes for Normal Conducting RF Gun

High-brightness electron beams are required for a number of applications, from advanced accelerators to 4th generation light sources. Noticeable interest resides in the development of high in-pulse average current (0.5 - 1 A) and emittance below 10 mm-mrad, high brightness electron beams for both accelerator and light source applications, such as synchrotrons and THz emitters. The current technologies for producing such beams are the RF photo-injector, driven by an expensive laser system, and thermionic guns, where high heat-load needs to be applied. Both result in high cost, large size and poor reliability. Due to the elimination of the laser and thermionic emitter, CNT cathodes are very robust, long-lived and easy in their processing and handling. After our successful experiment at FermiLab where the first CNT cathode was tested inside RF environment, RadiaBeam Systems proposes to further investigate the use of Carbon-Nanotube (CNT) cathode RF electron gun in order to achieve improved alpha magnet compression ratio and higher peak current, in the context of the THz source developed by RadiaBeam and Advanced Photon Source at ANL. Upon demonstration of reliable operation, CNT cathode RF guns will be viable substitutes for thermionic cathodes for continuous-wave operation. RadiaBeam will be to perform an optimized design of a Normal Conducting RF gun able to handle high currents from the CNT cathodes and at the same time evaluate and analyze possible solutions to the issues we learned from our first experiments with CNTs. The goal of the Phase I project is to perform high voltage DC tests, both CW and pulsed, of various and different cathode samples produced via CVD deposition. Moreover, RadiaBeam will examine the feasibility of the proposed CNT cathode RF gun, to optimize the RF gun to allow efficient bunch compression and acceleration of the beam and to prepare for fabrication and testing in Phase II. Current sources of high-quality, high-energy electrons are large, expensive and difficult to maintain. RadiaBeam Systems will develop a compact, ruggedized source of high quality electrons for applications ranging from research to cancer therapy and medical imaging. Commercial Applications and Other Benefits : High-brightness, high-current electron beams are required for a number of applications, including advanced accelerators, linear colliders, X-ray free-electron lasers (FELs), energy recovery Linacs (ERLs) and inverse Compton scattering (ICS) for research, medicine, and homeland security.