Studies of Hydrogen Atoms in High-Temperature Plasmas by Laser Fluorescence Spectroscopy at Balmer Series

Abstract

Technique of the laser fluorescence spectroscopy at Balmer series, for studies of hydrogen behaviour in high-temperature plasmas, was critically examined in terms of atomic hydrogen sources, SN ratios for measurements by Balmer alpha and beta fluorescence, and hardwares (tunable dye lasers and detection optics). It was concluded that Balmer alpha gave better SN ratio for all conditions investigated. In addition, detection limit and the means of improving the SN ratio were shown. Based on these discussions, atomic hydrogen in RFC-XX-M mirror-cusp device was measured, firstly to verify the above argument, and then to study the origin and behaviour of hydrogen atoms in the machine.