Observation of Molecular and Atomic Ions in Recombination Plasma

Abstract

Measurements of the densities of the molecular and atomic ions (n_H⁺, n_H2⁺, n_H3⁺) were carried out in hydrogen recombination plasma in the linear divertor plasma simulator, TPD-SheetIV. The molecular and atomic ion currents were detected using an omegatron mass analyzer. The ground-state vibrational temperature of hydrogen molecules T_vib is obtained by measurement with VUV emission spectroscopy. Taking into account of T_vib, a zero-dimensional model using the relevant rate balance equations was found to predict the observed dominant ion.