死に続ける女・葵上 -その機能的側面からのアプロ－チ-

Abstract

7 pages, 5 figures, 2 tables.-- Printed version published May 11, 2006.The chemical composition of a low pressure hydrogen DC plasma produced in a hollow cathode discharge has been measured and modelled. The concentrations of H atoms and of H+, H2+ and H3+ ions were determined with a combination of optical spectroscopic and mass spectrometric techniques, over the range of pressures (p∼0.008-0.2 mbar) investigated. The results were rationalized with the help of a zero-order kinetic model. A comparatively high fraction (∼0.1 ± 0.05) of H atoms, indicative of a relatively small wall recombination, was observed. Low ionization degrees (< 10-4) were obtained in all cases. In general, the ionic composition of the plasma was found to be dominated by H3+, except at the lowest pressures, where H2+ was the major ion. The key physicochemical processes determining the plasma composition were identified from the comparison of experimental and model results, and are discussed in the paper.The SEUID of Spain (Projects FTN2003-08228-C03-03, FIS2004-00456) and the CSIC-CAM (Project 200550M016) are gratefully acknowledged for financial support.Peer reviewe