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Brown, L. R.

Publications and source records attributed to Brown, L. R..

At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1986

Evidence for the presence of the 802.7/cm band Q branch of HO2NO2 in high resolution solar absorption spectra of the stratosphere

Stratospheric solar absorption spectra recorded at about 0.01/cm resolution by the ATMOS (Atmospheric Trace Molecule Spectroscopy) Fourier transform spectrometer during the Spacelab 3 Shuttle mission (4/30-5/6/85) show a weak absorption feature covering about 802.5-803.3/cm. This feature is identified as the unresolved Q branch of the 802.7/cm band of HO2NO2 and profiles for 31 deg N and 47 deg S are reported.

Rinsland, C. P.↗
NASA NTRS1986

Detection of carbonyl fluoride in the stratosphere

Infrared solar absorption spectra of the stratosphere recorded at a resolution of 0.01/cm by the ATMOS (Atmospheric Trace Molecule Spectroscopy) instrument from onboard Spacelab 3 (04/30 to 05/6/85) have revealed the existence of many previously unobserved absorption features in the 1925 to 1960/cm and 1249 to 1255/cm regions and one at 774/cm. On the basis of comparisons with laboratory spectra, these features have been identified as belonging to the nu1, nu4, and nu6 bands of carbonyl fluoride, respectively. Volume mixing ratios of COF2 between 17 and 40 km have been deduced from analysis of the nu1 and nu6 bands.

Rinsland, C. P.↗
NASA NTRS1986

The GEISA spectroscopic line parameters data bank in 1984

The 1984 update of the GEISA data bank, containing spectroscopic information on 323,521 lines corresponding to 36 molecules and 79 isotopic species in the spectal range 3 x 10 to the -6th/cm to 17,879/cm, is discussed. The bank compiles parameters describing the radiation absorption or emission properties of gases involved in the atmospheres of the earth and planets. Values of a new exponent which summarized the variation of the collision halfwidth with temperature are given for 10 molecules. Six new molecules, HOCl, N2, CH3Cl, H2O2, H2S, and HCOOH, are included in this edition.

Husson, N.↗
NASA NTRS1985

Comparison of the frequencies of NH3, CO2, H2O, N2O, CO, and CH4 as infrared calibration standards

The absolute accuracies of infrared calibration standards for the line positions have been investigated using a 0.0056-kayser-resolution (unapodized) Fourier-transform spectrum recorded from 550 to 5000 kayser. The spectrum has been obtained using a multicell arrangement containing the various molecular species. Detailed comoparisons reveal that standards for CO2, CH4, and N2O obtained from laser research and NH3 from Fourier-transform spectrometer research are consistent within the accuracies of the present data (+ or 0.0001 kayser). However, certain N2O, H2O, and CO values in the 1100-to 2300 kayser region are systematically high by 0.0001 to 0.0004 kayser. Correction factors for the H2O and CO standards are obtained to bring these into agreement with the laser values. In addition, corrected values for the 2nu-2 and nu-1 bands of N2O at 9 microns are reported.

Brown, L. R.↗
NASA NTRS1985

Spectroscopic database

Several aspects of quantitative atmospheric spectroscopy are considered, using a classification of the molecules according to the gas amounts in the stratosphere and upper troposphere, and reviews of quantitative atmospheric high-resolution spectroscopic measurements and field measurements systems are given. Laboratory spectroscopy and spectral analysis and prediction are presented with a summary of current laboratory spectroscopy capabilities. Spectroscopic data requirements for accurate derivation of atmospheric composition are discussed, where examples are given for space-based remote sensing experiments of the atmosphere: the ATMOS (Atmospheric Trace Molecule) and UARS (Upper Atmosphere Research Satellite) experiment. A review of the basic parameters involved in the data compilations; a summary of information on line parameter compilations already in existence; and a summary of current laboratory spectroscopy studies are used to assess the data base.

Husson, N.↗
NASA NTRS1983

AFGL atmospheric absorption line parameters compilation - 1982 edition

The latest edition of the AFGL atmospheric absorption line parameters compilation for the seven most active infrared terrestrial absorbers is described. Major modifications to the atlas for this edition include updating of water-vapor parameters from 0 to 4300 per cm, improvements to line positions for carbon dioxide, substantial modifications to the ozone bands in the middle to far infrared, and improvements to the 7- and 2.3-micron bands of methane. The atlas now contains about 181,000 rotation and vibration-rotation transitions between 0 and 17,900 per cm. The sources of the absorption parameters are summarized.

Rothman, L. S.↗
NASA NTRS1982

Methane line parameters for the 2.3-micron region

A new compilation of methane line parameters for the 4136-4666-per cm region has been obtained using experimental positions and intensities combined with known quantum assignments from the literature. Positions and intensities measured directly from the observed spectrum by computer are reported with accuracies of + or - 0.0005 per cm and 2%, respectively, for single unblended absorptions.

Brown, L. R.↗
NASA NTRS1981

AFGL trace gas compilation - 1980 version

A new edition of the AFGL trace gas compilation is now available. Absorption line parameters of positions, intensities, and half-widths are given for the major bands of thirteen gases covering the spectral region from 0 to 10,000/cm. In addition to updating the original gases (NO, SO2, NO2, and NH3), the molecules HNO3, OH, HF, HCl, HBr, HI, ClO, OCS, and H2CO have been added to the compilation. The sources for the additions and modifications are described.

Rothman, L. S.↗
NASA NTRS1981

Line parameters of methane from 2385 to 3200/cm

A list of new methane line parameters for the 2385-3200 cm region included in the Air Force Geophysical Laboratory's compilation of molecular line parameters is presented. Line positions were determined by computer computations from Fourier transform spectrometer data using a Kitt Peak subroutine. With the exception of class IV lines, all line strengths were determined by the method of equivalent widths. Additional line strengths were measured from spectra taken at cold sample temperatures so that lower state transition energies could be determined experimentally. Observed line positions and strengths are given for 8076 absorptions with strengths greater than 3.3 x 10 to the -24 cm/molecule.

Toth, R. A.↗
NASA NTRS1978

Line intensities of methane in the 2700-2862-kayser region

Individual strengths and wave numbers of 2080 methane absorption lines have been measured between 2700 and 2862 kaysers at an average resolution of 0.023 kayser using a grating spectrometer. The results include all lines with strengths greater than 0.00003 per sq cm/atm observable at 296 K with a maximum path of 32 m and a pressure of 4 torr.

Hunt, R. H.↗
NASA NTRS1975

Study to define and verify the personal oral hygiene requirements for extended manned space flight: Oral physiology and microbiology in Skylab manned space missions

Methods for metabolic fingerprinting of pathogenic oral bacteria were developed and the effects of Skylab missions on salivary electrolyte levels were studied. High resolution gas liquid chromatographic (GLC) and pyrolysis-GLC procedures were used to obtain metabolic profiles of closely related bacteria associated with dental caries and periodontal disease. It was found that the GLC procedures provide a practical and reproducible means of obtaining metabolic markers for identifying closely related strains of these organisms. Fractions of stimulated whole saliva samples from the prime and back-up crews of the three Skylab missions were used to measure salivary electrolyte concentrations. All the electrolytes previously reported as having increased in urine and feces during the missions were assessed. Sodium, potassium, calcium, magnesium, phosphorous and chloride were studied. A decrease in sodium and an increase in magnesium were observed, but the mineral imbalances attributable to the mission-related increases in urinary electrolytes were not detected.

Brown, L. R.↗