OPACITY OF LOW TEMPERATURE AIR
Abstract
Emission spectrograms with 0.2 Angstrom resolution have been recorded for shock-heated air, oxygen, nitrogen, and nitrous oxide for temperatures from 6,000 to 12,000 degrees Kelvin and densities from 0.1 to 3.3 normal. The beta and gamma band systems of nitrous oxide were not observed in these spectra, leading to the conclusion that Bethke's f-values are at least a factor of two too high. A SACHA peak-to-minimum fit to the experimental profile of singly ionized molecular nitrogen 3,914 Angstrom band head was found for a Lorentz line width of 1.9 per centimeters for the condition of 9,500 degrees Kelvin and 0.125 normal density in pure nitrogen. An upper limit for the molecular oxygen-atomic oxygen collision cross section of less than or equal to 2 x 10 to the -14th power square centimeters has been obtained from analysis of oxygen Schumann-Runge emission lines for the condition of 8,400 degrees Kelvin and 0.3 normal density. Absolute intensity measurements of nitrogen continuum radiation in the molecular regime below 12,000 degrees Kelvin have failed to show the intensity predicted by Boldt's negatively charged atomic nitrogen photodetachment cross section. The addition of lithium oxide to shocks in oxygen has failed to show any real evidence of the negatively charged atomic oxygen photoelectric edge at 3,6000 Angstroms. However, SACHA experimental analyses of the oxygen Schumann-Runge rotational lines at 3,400 Angstroms has yielded some qualitative evidence of the existence of an edge underlying the molecular oxygen rotational line.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1965
- Accession Number
- AD0476380
Entities
People
- D. E. Buttrey
- H. R. Mcchesney
Organizations
- Lockheed Martin Missiles and Space