Electron beam generation and transport in a backward wave oscillator experiment

Summary form only given. The UNM (University of Mexico) backward wave oscillator device consists of a high-power relativistic electron beam propagating through a slow wave structure immersed in a strong axial magnetic field. A hollow cathode powered by a Nereus Marx generator is used to produce a 600-keV electron beam with I_b=2-5 kA. The initial slow wave structure that will be used has a sinusoidally rippled wall with period Z₀ =1.1 cm, r_min=0.85 cm, r_max=1.45 cm, and length L=19.8 cm. The axial magnetic field is produced by a solenoidal coil that is powered by an ignitron switched 50-kJ capacitor bank. Field strengths of up to 20 kG will be produced. In addition to the experimental effort, the dispersion characteristics and expected growth rates are being calculated for the initial slow wave structure and the dozen other structures that will be used. MAGIC simulations of the experiment are also being initiated. The goal is to characterize the dependence of microwave power output and start current on the fundamental parameters of a slow wave structure