AFTERGLOW STUDIES IN NITROGEN,
Abstract
The temporal behavior of the N(+), N2(+), N3(+) and N4(+) ions in decaying nitrogen plasmas as well as that of the afterglow light intensity was studied in the pressure range of about 0.1 Torr to 1.7 Torr. The plasma container was a glass cylinder covered by a molybdenum film. An electric quadrupole mass spectrometer was used for the ion density studies while a light spectrometer allowed a determination of the spectral distribution of the afterglow light. The analysis of the light intensity decay curves resulted in a method of measuring the surface catalytic efficiency for the recombination of nitrogen atoms at the plasma boundary. An analysis of the N2(+) density decay curves at low pressures revealed that these ions are produced in the afterglow by collisions between metastable molecules N2(x) and N2(y). These metastable molecules are (1) very ineffectively destroyed at the plasma boundary, (b) produced in the afterglow period by the atomic recombination process and (c) responsible for part of the afterglow light emission. The value of the electron temperature, determined through consideration of the losses of the N(+) ions, varied from 1600K to 4500K in the pressure range studied. Evidence was obtained for afterglow electron heating by ionizing collisions between metastable molecules and by superelastic collisions between electrons and vibrationally excited ground state molecules. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1967
- Accession Number
- AD0657355
Entities
People
- H. J. Oskam
- R. E. Lund
Organizations
- University of Minnesota