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Giver, L. P.

Publications and source records attributed to Giver, L. P..

53 records · Page 3

Intensity measurements for the /2, O/ gamma-band of O2, b 1Sigma-g/+/ - X 3Sigma-g/-/

Line intensities for the P sub P and P sub Q branches of the (2-O) vibrational band of the magnetic dipole electronic transition for the oxygen red system at 6280 A were measured, and the sum of the R sub R and R sub Q branch intensities was taken. A large number of repetitive spectral scans were required for accuracy, because of low absorption values even at optical path lengths from 300 to 600 m. A total of 557 individual measurements of P-branch lines yielded an intensity value for the P-branches, and equivalent widths for 24 spectral scans yielded an intensity value for the R-branch. R-branch to P-branch intensity ratios were taken for the A-band, B-band, and gamma-band (respectively, O-O at 7620 A, 1-O at 6880 A, and 2-O at 6280 A). Intensities for some rotational lines are found, and effects of combined rotation-vibration interaction are probed.

Miller, J. H.↗

A laboratory Atlas of the 5 nu-1 NH3 absorption band at 6475 A with applications to Jupiter and Saturn

A complete atlas of the 5 nu-1 absorption band of NH3 is presented together with measurements of the total band intensity, line intensities, and self-broadening coefficients. The spectrum, which is displayed in the interval from 6418 to 6550 A, was obtained photoelectrically at a pressure of 0.061 atm, and many more lines were seen in this spectrum than in a previous one obtained at a pressure of 0.39 atm. The band intensity is used to derive the NH3 abundance in the atmospheres of Jupiter and Saturn, and the abundances in a single vertical path are found to be about 10 m amagat for Jupiter and 2 m amagat for Saturn. These results are shown to be in agreement with previous results obtained from higher resolution photographic spectra.

Giver, L. P.↗

Density-dependent frequency shift of the hydrogen S2/1/ quadrupole line

An optical parametric oscillator pumped with an Nd:YAG laser was used in the investigations along with a White cell and a scanning spectrometer. The frequency of the S2(1) line was measured at a temperature of about 293 K over the density range from 1 to 4.3 amagat with the aid of a technique reported by Douglas and Sharma (1953). It was found that the obtained data are in good agreement with measurements conducted by Fink et al. (1965).

Chackerian, C., Jr.↗

Does spectroscopic evidence require two scattering layers in the Venus atmosphere.

Comments on Hunt's (1972) conclusion that the phase variation of lines in the 7820- and 7883-A CO2 bands is due to the presence of two scattering layers in the Venusian atmosphere. It is shown that the increase of equivalent width with phase between 0 and 90 deg noted by Hunt in the data by Gray Young et al. (1971) does not necessarily require a two-layer model of scattering in the Venusian atmosphere and that this increase may be due to the strong backward lobe in the Venusian cloud phase function. Hunt, in a reply, notes that Regas et al. incorrectly use in their analysis Hansen's (1969) data which are for a homogeneous planetary atmosphere, while Hunt used an inhomogeneous model of the Venusian atmosphere. In addition, further evidence to support Hunt's claim for a multilayered structure of the upper Venusian clouds is presented.

Regas, J. L.↗

Theoretical interpretation of the Venus 1.05-micron CO2 band and the Venus 0.8189-micron H2O line.

The synthetic-spectrum technique was used in the analysis. The synthetic spectra were constructed with a model which takes into account both isotropic scattering and the inhomogeneity in the Venus atmosphere. The Potter-Hansen correction factor was used to correct for anisotropic scattering. The synthetic spectra obtained are, therefore, the first which contain all the essential physics of line formation. The results confirm Potter's conclusion that the Venus cloud tops resemble terrestrial cirrus or stratus clouds in their scattering properties.

Regas, J. L.↗