抄録
Electric propulsion is known as a high-efficiency method for deep space explorers. However, most of methods have electrodes contacting directly with plasma, and its lifetime is limited by electrodes' erosion. We have been developing electrodeless electric propulsion systems in order to overcome this problem, and carried out optical measurements using a high-speed camera and monochromators to estimate high-density helicon plasma performance in our systems. Electron and neutral particle density profiles have been measured by a high-speed camera, and velocity of singly-charged Ar Ion by a high-resolution monochromator. Preliminary experiment of a spectroscopic method using an intensity ratio based on a collisional radiative model with CCD monochromator has been performed additionally. Since plasma parameters obtained by these methods have a good agreement with results by an electrostatic probe, non-invasive optical measurements presented here can demonstrate useful tools for estimating the plasma parameter of an electric propulsion system.
