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Participants at the 13th Airborne Earth Science Workshop reported science research and applications results with spectral images measured by the NASA Airborne Invisible/Infrared Imaging Spectrometer (AVIRIS).

Simulated equivalent width data of weak lines in occultation spectra have been analyzed to retrieve both the atmospheric temperature profile and the tangent heights of the rays. The SNR of these widths varied from 5 to 100. The mixing ratio of the absorbing gas and sea level pressure were assumed but not the satellite position. Temperature and tangent heights with accuracies of 1 K and 0.25 km, respectively, were determined from lines with temperature-dependent and temperature-independent intensities.

An atlas of CH4 lines between 700 and 5,500 cm(-1) obtained from long-path-length samples at 296 K is presented. Many of the line centers are marked and their positions tabulated.

Simulated equivalent width data of weak lines in solar occultation spectra were analyzed to retrieve both the solar atmospheric temperature profile and the tangent heights of the rays. It was assumed that the mixing ratio of the absorbing gas was known, but it is not necessary to know the satellite height. By analyzing lines with temperature dependent and temperature independent intensities, temperatures accurate to 1 K and tangent heights to 0.25 km were determined over the range 20 to 90 km.

(Previously announced in STAR as N82-32438)

The parameters of three bands of CO2 near 2600 per cm have been determined by the nonlinear least squares method of whole-band analysis. Careful modeling of the effect of the Fourier transform spectrometer on the spectrum has made it possible to reduce the difference between the observed and calculated spectra to values close to the estimated noise in the experimental spectrum. In particular, it is found necessary to model the effects of phase error even though these are difficult to observe in the experimental spectra.

The band constants of CO2 bands near 2600 per cm have been estimated by the nonlinear least squares method and spectral curve fitting. The synthetic spectra calculated from these constants predict experimental values accurately and give very similar values for the line positions (to within 0.003 per cm for all but the weakest lines).

The intensities, widths, and positions of lines of three CO2 bands near 2750/cm were determined. The results are in general agreement with other measured and estimated values.

An atlas of CO2 lines obtained from long path length samples at 296 K is presented. Many of the line centers are marked and their positions tabulated.

Whole band analysis, a method of obtaining band parameters from spectra by nonlinear least squares fitting of calculated to observed spectra, has been applied to bands of N2O and CO2. The retrieved N2 broadened widths of the 02(0)00 - 00(0) and 12(0)0 - 00(0)0 bands of N2O suggest that the air broadened widths on the AFGL listing are about 10% high. The intensities and (C-12)(O-16)2 broadened widths of the 20002-00001 and 21102-01101 bands of (C-12)(O-16)(O-18) and the 20002-00001 band of (C-12)(O-16)(O-17) have also been determined.

Solar absorptance of satellite coatings measured as function of angle of incidence, using thermal vacuum technique

Thermal vacuum technique for measuring solar absorptance of satellite coatings as function of angle of incidence

Solar absorptance by satellite coating with measurement as function of incidence angle using thermal vacuum