A survey of microwave inverse FEL and inverse cerenkov accelerators

A Microwave Inverse FEL Accelerator (MIFELA) and a Microwave Inverse Cerenkov Accelerator (MICA) are currently under construction at the Yale Beam Physics Laboratory. MIFELA and MICA will share the same injector, a thermionic cathode rf gun that should furnish 5 psec, 6 MeV, 0.2 nC electron pulses spaced by 350 psec, using microwave power of many MW provided from a 2.85 GHz klystron. MIFELA is to operate with ∼4Mw of 11.4 GHz microwave power in the TE11 mode, with beam injection into each fourth rf cycle; a variable pitch and field undulator together with a guide magnetic field are present as well. MICA will operate at 2.85 GHz using an alumina-lined waveguide driven in the TM01 mode; the phase velocity is just below c, with no guide field. MIFELA produces a beam of spiralling electrons, while MICA makes an axially-directed beam. This is a survey of the operating principles of these smooth-bore open-quotes tabletopclose quotes accelerators (∼15MeV) as they are understood prior to operation. copyright 1997 American Institute of Physics