MULTIPACTOR DISCHARGE EXPERIMENTS

Abstract : An experimental investigation of the multipactor discharge mechanism was conducted to determine the effect of dc bias, electrode materials, and electrode geometry on the RF voltage required for initiation of the discharge. The experiments showed that most of the commonly used aerospace materials support multipactor discharges, and that the discharge can occur over a wide range of bias voltages. The experiments were conducted with a parallel-plate geometry, a coaxial geometry and with the cone-plane configuration of a discone antenna. All of the coaxial electrode geometries support multipactor discharges, and the discone configurations with cone half-angles greater than 60 degrees supported the discharges. Attempts to measure the RF power dissipated by the discharge indicated that this power was relatively small, so the main detrimental effect of the multipactor discharge on RF systems in space will be in detuning high-Q circuits and in the possibility of more serious failure mechanisms being induced by the multipactor discharge. (Author)