HR: 1330h
AN: SA12A-1084    [PDF]
TI: Photodissociation and Photodissociative Ionization Excitation Emissions from Molecular Nitrogen in the Thermosphere: Results from Analysis of FUSE Dayglow Measurements
AU: * Bishop, J
EM: jbishop@uap2.nrl.navy.mil
AF: E O Hulburt Center for Space Research, Naval Research Laboratory, Code 7640, Washington, DC 20375 United States
AU: Stevens, M H
EM: stevens@uap2.nrl.navy.mil
AF: E O Hulburt Center for Space Research, Naval Research Laboratory, Code 7640, Washington, DC 20375 United States
AU: Feldman, P
EM: pdf@pha.jhu.edu
AF: Department of Physics and Astronomy, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218 United States
AB: Photodissociation and photodissociative ionization (PDI) excitations of molecular nitrogen result in a number of relatively bright far ultraviolet emission features in the dayglow in addition to the more commonly analysed emissions generated by photoelectron impact (e.g., the N$_{2}$ LBH band system). Provided spectral resolutions are high enough, several N$_{2}$ PDI features (e.g., N$^{+}$ 1085 \AA ) are of considerable interest as remote sensing alternatives to N$_{2}$ LBH. Recent work with Astro-1/Hopkins Ultraviolet Telescope (HUT) data [Bishop and Feldman, {\it JGR}, {\it 108}(A6), 1243, doi:10.1029/2001JA000330, 2003] made this point but also showed that the emission ratios of the N$_{2}$ PDI N*,N$^{+}$ lines in the dayglow are not consistent with the ratios of Samson et al [{\it J Chem Phys}, {\it 95}, 717-719, 1991] obtained with a synchrotron light source. The Far Ultraviolet Spectroscopic Explorer (FUSE) dayglow measurements reported in Feldman et al [{\it JGR}, {\it 106}, 8119-8129, 2001] are of sufficient spectral resolution to provide reference intensities and emission ratios. First-principles model analysis results for the FUSE LWRS (``low resolution'', 0.38 \AA ) dayglow data from September 1999 for N$_{2}$ PDI N*,N$^{+}$ and other N$_{2}$ features are presented and compared with the Astro-1/HUT analysis results.
DE: 0310 Airglow and aurora
DE: 0355 Thermosphere--composition and chemistry
DE: 2423 Ionization mechanisms
DE: 7549 Ultraviolet emissions
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting