OPTICAL EXCITATION OF OXYGEN BY 20 TO 100KEV PROTONS,
Abstract
A spectroscopic study was made of the light (3000 5700 A) emitted from impact of 18 to 102-kev protons with molecular oxygen at pressures from 1 to 400 milliTorr. The dominant emissions were from O(+) and O2(+). Only a few weak O lines were observed since the major ones lie outside the spectral range measured. A single weak O(++) line was identified, indicating that excited O(++) was not a major product of the collisions. No O2 spectra were detected. At lower proton energies, the H-beta line was prominent, indicating capture of electrons into excited states by the incident H(+). Absolute emission cross sections were determined for all major transitions observed, and absolute excitation cross sections were calculated for several O(+) states. The brightest O(+) multiplet (3s4P - 3p4D?) had a maximum emission cross section of 2.2 x 10 to the -19th power sq cm, which occurred at a proton energy of about 30 kev. The variation of emission intensities with target gas pressure and beam current were investigated in order to determine the occurrence of secondary excitations. Comparisons are made of the laboratory spectra with auroral spectra. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1965
- Accession Number
- AD0615466
Entities
People
- Doran J. Baker
- Fon R. Brown
- John J. Merrill
- R. Gary Layton
Organizations
- Utah State University