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Cook, G. R.

Publications and source records attributed to Cook, G. R..

13 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Static noise tests on modified augmentor wing jet STOL research aircraft

Noise measurements were made to determine if recent modifications made to the bifurcated jetpipe to increase engine thrust had at the same time reduced the noise level. The noise field was measured by a 6-microphone array positioned on a 30.5m (100 ft) sideline between 90 and 150 degrees from the left engine inlet. Noise levels were recorded at three flap angles over a range of engine thrust settings from flight idle to emergency power and plotted in one-third octave band spectra. Little attenuation was observed at maximum power, but significant attenuation was achieved at approach and cruise power levels.

Cook, G. R.↗
NASA NTRS1980

Quantitative laboratory spectra and spectral line parameters for the nu2 and nu4 bands of PH3 applicable to spectral radiative models of the atmosphere of Jupiter

Quantitative laboratory PH3 absorption spectra were obtained in the 800-1350/cm region, at approximately 0.05/cm resolution, with gas amounts corresponding to observed PH3 absorptions in the atmosphere of Jupiter. A compilation of spectral line positions, intensities and ground state energies has been generated for the nu2 and nu4 bands of PH3. Line-by-line calculations have been compared with the experimental spectra.

Goldman, A.↗
NASA NTRS1980

New atlas of IR solar spectra

Over 4500 absorption lines have been marked on the spectra and the corresponding line positions tabulated. The associated absorbing telluric or solar species for more than 90% of these lines have been identified and only a fraction of the unidentified lines have peak absorptions greater than a few percent. The high resolution and the low Sun spectra greatly enhance the sensitivity limits for identification of trace constituents.

Goldman, A.↗
NASA NTRS1979

Identification of the V3 vibration-rotation band of CF4 in balloon-borne infrared solar spectra

Infrared solar spectra in the 850 to 1350/cm region, at 0.02/cm resolution, were obtained during a balloon flight made on 27 October 1978 from Alamogordo, New Mexico. Analysis of the 1275-1290/cm region indicates that the atmospheric absorption lines of CH4, N2O, H2O, HNO3 and CO2 near 1283/cm are super-imposed on a broader absorption feature which we interpret as due to the V3 band of CF4. Fine structure of CF4 is also identified. Preliminary estimates from the sunset spectra show approximately 75 pptv CF4 near 25 km.

Goldman, A.↗
NASA NTRS1978

Determining crustal strain rates with a spaceborne geodynamics ranging system. 2: Station coordinate analysis

The use of a spaceborne geodynamics ranging system for determining crustal strain rates is analyzed. The use of site coordinates rather than intersite baseline distances for the strain rate determinations is emphasized. After discussing the analytical techniques which are to be employed, numerical results are presented which suggest that the use of site coordinates would result in a 20-70% improvement in the precision of the deduced values of straining. Precision of a few parts in 10 to the 9th power would be achievable with simple geometrics and a decade or two of measurements; precisions of a few parts in 10 to the 8th power would be achievable in a few years. A consideration of possible correlations among the derived target site coordinates leads to the conclusion that, with the proper choice of coordinate systems, the correlations can be made small and non-detrimental to the strain rate determinations.

Cohen, S. C.↗
NASA NTRS1978

Determining crustal strain rates with spaceborne geodynamics ranging system data. 1: Baseline analysis

A satellite-borne laser ranging system is proposed that is capable of making highly precise geodetic measurements over baselines ranging from a few tens of kilometers to several hundred kilometers. The precision with which crustal strain rates are derived from measurements made with this system is analyzed by using simple site configurations, intersite distances of about 25-70 kilometers, and measurement programs ranging from a few years to fifteen years. It is concluded that precisions of several parts in 10 to the 9th power per year are achievable. Compared to the expected shear strain rates of about 7 x 10 to the minus 7th power yr/1, this produces very favorable signal-to-noise ratios.

Cohen, S. C.↗
NASA NTRS1978

Identification of the nu-2 vibration-rotation band of ammonia in ground level solar spectra

Comparison of infrared solar spectra in the 750 to 950 kayser region obtained during sunrise and sunset shows that a number of features due to the nu-2 NH3 band are present on the sunset spectra but are indicated by only a trace on the sunrise spectra. The sunset path shows approximately 0.007 atm-cm NH3, and the reason for the discrepancy between sunrise and sunset spectra is not known. The ground-based measurements at Denver were obtained with a 0.06 kayser resolution.

Murcray, D. G.↗
NASA NTRS1973

Photodissociation continuums of N2 and O2.

Dissociation continuum cross sections for N2 and O2 have been determined from previously measured total absorption and ionization cross sections. Several dissociation continuums were found for each molecule. Some of these continuums were attributed to specific dissociation products in which the dissociation products are in excited states. The upper-atmosphere emission rates resulting from these photodissociative excitation processes have been calculated for the N I 10,400-A and O I 1356-A lines. The results indicate, particularly for the oxygen line, that these photodissociative processes may be important in the dayglow.

Cook, G. R.↗
NASA NTRS1971

Device measures conductivity and velocity of ionized gas streams

Coaxial arrangement of primary coil and two sensing secondary coils contained inside slender quartz tube inserted into ionized stream permits simultaneous determination of conductivity and linear velocity. System results agree favorably with theory.

Cook, G. R.↗