HR: 1330h
AN: SA12A-1083    [PDF]
TI: Lyman-Birge-Hopfield Band Observations from ARGOS: Vibrational Populations and Their Altitude Dependence
AU: * Eastes, R W
EM: reastes@mail.ucf.edu
AF: Florida Space Institute, MS-FSI, Kennedy Space Center, FL 32899 United States
AU: Budzien, S A
AF: Naval Research Laboratory, Code 7607, Washington, DC 20375-5352 United States
AU: Dymond, K F
AF: Naval Research Laboratory, Code 7607, Washington, DC 20375-5352 United States
AU: Thonnard, S E
AF: Naval Research Laboratory, Code 7607, Washington, DC 20375-5352 United States
AU: Nicholas, A C
AF: Naval Research Laboratory, Code 7607, Washington, DC 20375-5352 United States
AU: McCoy, R P
AF: Office of Naval Research, Code 321SR 800 N Quincy St., Arlington, VA 22217 United States
AB: The N$_2$ Lyman-Birge-Hopfield (LBH) bands (a-X transition) extend throughout the Earth's far-ultraviolet spectrum in the dayglow and aurora. LBH band emissions are important for remote sensing of the Earth's thermosphere, used in both limb-scanning techniques that retrieve N$_2$ and O$_2$ densities and in nadir-viewing techniques for retrieving the O/N$_2$ column density ratios. There is significant uncertainty in modeling the LBH emissions, yet reliable interpretation of remote sensing data depends on the ability to accurately model the emissions. Over the years a wide variety of a-state vibrational population distributions have been inferred from different remote sensing experiments. We present the vibrational population distributions from ultraviolet spectra collected by the High resolution Ionospheric and Thermospheric Spectrograph (HITS) aboard the Advanced Research and Global Observation Satellite (ARGOS). These high spectral resolution (~.2 nm) limb-scan data exhibit brighter emissions from the lower vibrational levels than would be expected from traditional models. The altitude- and latitude-resolved vibrational populations provide clues to the N$_2$ singlet excitation and cascade mechanisms that are key to correct interpretation of LBH observations.
DE: 0310 Airglow and aurora
DE: 0350 Pressure, density, and temperature
DE: 0355 Thermosphere--composition and chemistry
DE: 0358 Thermosphere--energy deposition
DE: 0394 Instruments and techniques
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting