*Hui-kuan FANG1, Yu-wei HSU2, Wen-hao CHEN2, Guo-hsiang JIANG2, Koichiro OYAMA3, Chio CHENG3
(1.Department of Physics, National Cheng Kung University, 2.Institute of Space and Plasma Sciences, National Cheng Kung University, 3.Plasma and Space Science Center, National Cheng Kung University)
Keywords:Plasma properties, space plasma operation chamber, back-diffusion plasma source, retarding potential analyzer, electron temperature and density probe, Langmuir probe
The space plasma operation chamber (SPOC), a research facility designed to calibrate and test satellite/rocket-borne instruments and study space plasma processes, is constructed at NCKU in 2009. It is a cylindrical chamber of 2m in diameter and 3m in length. Plasma is produced by two back-diffusion type sources installed at the center of both chamber sides. The sources produce ions of controllable drifting energy from a few ten to several hundred eV and density up to 106 cm-3. These ions are neutralized by thermal electrons emitted from Nickel cathodes, and collide with neutral molecules in the chamber of pressure ~2.2×10-4 Torr, and a plasma environment with ion temperature ~300K and electron temperature ~1000-3000K is formed in the chamber. This paper presents measurement results of a retarding potential analyzer (RPA), an electron temperature and density probe (TeNeP) and a Langmuir probe installed on the 2-axis moving system in SPOC. The thermal and beam component ion energy distributions at different distances from the ion source and the electron temperature/density spatial distributions in the SPOC will be presented. The collision process of ions with neutral molecules will also be discussed.