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Farmer, C. B.

Publications and source records attributed to Farmer, C. B..

88 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Line strengths of H2O and N2O in the 1900-kayser region

Laboratory measurements of the line strengths of H2O and N2O in the 1900-kayser spectral region are reported which were made with moderate resolution using a modification of a Michelson interferometer. The N2O analysis includes measurements of the line strengths of the P and R branches and the integrated strength of the Q branch of the nu-1 + nu-2(1) band as well as the integrated strengths of the Q branches of the nu-1 + nu-2(2) - nu-2 and nu-1 + nu-2(0) - nu-2(1) bands. The H2O data cover the region from 1830 to 1980 kaysers; they include line-strength measurements of 61 lines of the nu-2 band, 10 lines of the nu-2 band of H2(O-18), two lines of the nu-2 band of H2(O-17), and three lines of the 'hot' band transition 2 nu-2 - nu-2. The estimated uncertainties in the measured line strengths range from 7% to 20% for H2O, 10% to 25% for H2(O-18) and H2(O-17), and 4% to 8% for N2O.

Toth, R. A.↗
NASA NTRS1974

Infrared measurements of stratospheric composition

The observational techniques and results of IR measurements of the minor and trace molecular composition of the lower stratosphere are reviewed. Emphasis is given to those theoretical aspects of the formation of emission and absorption spectra which affect the quantitative interpretation of observational data in terms of the vertical distribution of observed molecular species. The principal experimental techniques currently being used are briefly reviewed, followed by a detailed summary of current knowledge of the abundances and spatial variability of the known minor constituents. The question of the determination of the minimum detectable concentration of a constituent molecule and its relationship to the instrumental parameters, the molecular transition intensities, and observation geometry is discussed; upper limit concentrations are given for some additional species of importance in current stratospheric studies.

Farmer, C. B.↗
NASA NTRS1973

Measurement of the abundance of several natural stratospheric trace constituents from high altitude aircraft

A summary report of the initial results obtained from near-infrared observations of the stratosphere from the Anglo-French SST Concorde is presented, together with the most recent results from previous flights aboard an Air Force NC-135. The measurements were made with a fast Fourier interferometer spectrometer operating in the 1.2- to 7.5-micron range of the infrared with a spectral resolution of 0.25 per cm. For the Concorde experiments, flight times and trajectories were selected which allowed the sun to be viewed near the horizon with the relative solar elevation angle held constant throughout the measurements. Results reported include the identification of features due to N2O, NO, NO2, CO, CO2, CH4, H2O and indications of their latitudinal variations.

Farmer, C. B.↗
NASA NTRS1972

Jupiter - Observation of deuterated methane in the atmosphere.

During May 1971 a number of whole-planet spectra of Jupiter were obtained. Strongly evident in the spectrum of Jupiter are several J-manifolds in the P-branch of a band of CH3D. It is believed that this is the first observation of deuterium in any astronomical source. The spectrum of Jupiter is shown together with the spectrum of the sun, and a representation of a ratio of the spectrum of Jupiter to that of the sun.

Beer, R.↗
NASA NTRS1972

The detection and mapping of water vapor in the Martian atmosphere.

The objectives of the water vapor investigations, to be carried out during the Viking missions, are described in the light of our current knowledge of Martian atmospheric conditions and the diurnal and seasonal variations of the water abundance. A discussion is given of the relative merits of the different experimental approaches which can be adopted for this purpose, followed by a summary of the detection limits achievable in the available spectral regions. These considerations led to the choice of a spectrometer operating in the 1.4-micron region, with a spectral resolution of approximately one wavenumber and a surface spatial resolution at periapsis of 3 by 24 km. The design of the spectrometer and the results of laboratory simulation tests which have been carried out to verify the expected instrumental performance are described.

Farmer, C. B.↗
NASA NTRS1972

The inference of temperature from the infrared spectra of planets.

The paper is concerned primarily with the determination of the temperature of planetary atmospheres from ground-based observations of the vibration-rotation spectra of their constituent gases. The paper is divided into two parts. The first is a discussion of the theoretical basis and analytical methods for the interpretation of planetary spectra formed by reflection of solar radiation, in the ideal case of a clear, nonscattering atmosphere; this is followed by a brief description of the effects of scattering in cloudy atmospheres on the formation of spectral lines and on the inferred temperatures. In the second part examples are given of the results which have been obtained for effective temperatures and thermal structures, for both the pure absorbing and the scattering cases, and these are compared with the results of flyby and entry probe measurements.

Farmer, C. B.↗
NASA NTRS1971

Global studies of atmospheric pollutants and trace constituents.

A high speed, high resolution, Fourier interferometer operating in the 1 to 5 micron spectral region can best meet the needs for remotely detecting and monitoring various molecular species in the atmosphere. An operational breadboard version of the instrument exists. Spectra obtained from ground sites in the Los Angeles area demonstrate the presence of several gases in the atmosphere. Two spectra in the 2.1 and 2.3 micron regions respectively are presented from which relative abundances of carbon dioxide and carbon monoxide are derived. Ground based operations and aircraft flights with the present instrument verify the potential operational capacity for a satellite instrument. A discussion is presented on the use of the instrument from a spacecraft.

Toth, R. A.↗
NASA NTRS1971

The strengths of H2O lines in the 8200 A region and their application to high dispersion spectra of Mars.

The improvement in the quality of spectroscopic plates taken in recent years in the search for water vapor in the atmosphere of Mars has dictated the need for improved laboratory data with which to interpret the spectra. This paper presents the results of measurements of the strengths of 41 lines of the 8200 A (211) water vapor band. The measured values show evidence of vibration-rotation interactions on the line intensities, beyond the principal stretching effect.

Farmer, C. B.↗