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Laboratory spectra have been obtained for HNO3 with a Michelson-type Fourier transform interferometer using absorption cells with path lengths of 10.3, 25.5, and 49.8 cm at temperatures of 240, 248, 283, and 294 K. The measurements lead to a total band intensity value of 642 plus or minus 5% per sq cm amagat, which is a temperature independent value after the gas density correction has been made. However, the temperature dependence of the spectral absorption coefficients is apparent in the 885 kayser region.

Values for mid-IR integrated band intensities of gaseous N(2)O(5) were determined at room temperature. The absorptions studied were at 1720, 1246, 743, and 557 cm(-1). The integrated intensities were 2204, 581, 685, and 699 atm(-1)-cm(-2), respectively. Implications of these results for the stratospheric detection of N(2)O(5) are discussed.

A new atlas of CH(4) lines in the 1120-1800-cm(-1) region has been generated, based on laboratory spectra taken with a Nicolet interferometer at 0.06-cm(-1) resolution with 635-cm path length at pressures of 0.98 Torr, 4.86 Torr, and 19.97 Torr. A compilation of line positions and line intensities includes 1339 CH(4) lines, several hundred of which have not been previously observed.

Absolute intensities of the vibration-rotation lines of the CO2 401II←000 band 7734 cm-1 are measured under high-resolution, low-pressure conditions by use of a White-type 25-m base-path, absorption cell together with a 5-m Czerny-Turner spectrometer. The total band intensity SB, the purely vibrational transition moment , and the vibration-rotation interaction constant ζ are calculated from the intensity measurements. The values obtained for these parameters are SB(401II) = (7.06±0.07) × 10-5 cm-2 atm-1293°K, = (3.08±0.03)×10-5 debye, and ζ = (2.5±0.5)×10-4. The intensity of the associated “hot band” 411II←010 is also determined and found to be SB(411II←010) = (0.53±0.02)×10-5 cm-2 atm-1293°K.

The functional aspects of the Large Probe Infrared Radiometer Instrument are presented taking into account the experiment's objective and the mission's constraints. The optical elements, including the detectors, are described and a brief review of the instrument's calibration is given.

Absolute line intensities and self-broadening coefficients have been measured at 197° and 294°K for the 201II ← 000 band of 12C16O2 at about 4978cm-1. The vibration-rotation factor (FVR), the purely vibrational transition moment (∣R(O)∣), and the integrated band intensity (Sband) are deduced from the measurements. The results are: FVR(m)=1+(0.24±0.08)x10-4m+(0.55+0.21)x10-4m2, ∣R(O)∣= (4.340±0.008x10-3 debye, Sband=96372±190cm-1km-1atm-1STP. The results for self-broadening coefficients, as well as for individual vibration-rotation lines, are presented in the text.

The integral band intensity of the pure rotational absorption of SO2 gas has been determined from far-i.r. spectra. From the curve of growth, the value at 298°K is found to be Sob = 35.2±1.5atm-1 -cm-2. The entire set of experimental data has been analyzed using an absorption band model. The derived intensity agrees with that obtained from the curve of growth to be better than 10%. This result should be of value in connection with atmospheric models of the planet Venus.

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.

The four entry probes of the Pioneer Venus mission measured the radiative net flux in the atmosphere of Venus at latitudes of 60 deg. N, 31 deg. S, 27 deg. S, and 4 deg. N. The three higher latitude probes carried instruments (small probe net flux radiometers; SNFR) with external sensors. The measured SNFR net fluxes are too large below the clouds, but an error source and correction scheme have been found (H. E. Revercomb, L. A. Sromovsky, and V. E. Suomi, 1982, Icarus 52, 279-300). The near-equatorial probe carried an infrared radiometer (LIR) which viewed the atmosphere through a window in the probe. The LIR measurements are reasonable in the clouds, but increase to physically unreasonable levels shortly below the clouds. The probable error source and a correction procedure are identified. Three main conclusions can be drawn from comparisons of the four corrected flux profiles with radiative transfer calculations: (1) thermal net fluxes for the sounder probe do not require a reduction in the Mode 3 number density as has been suggested by O.B. Toon, B. Ragent, D. Colburn, J. Blamont, and C. Cot (1964. Icarus 37, 143-160), but the probe measurements as a whole are most consistent with a significantly reduced mode 3 contribution to the cloud opacity; (2) at all probe sites, the fluxes imply that the upper cloud contains a yet undetected source of IR opacity; and (3) beneath the clouds the fluxes at a given altitude increase with latitude, suggesting greater IR cooling below the clouds a( high latitudes and water vapor mixing ratios of about 2-5 x 10(exp -5) near 6 deg., 2-5 x 10(exp -11) near 30 deg., and less than 5 x 10(exp -4 ) near the equator. The suggested latitudinal variation of IR cooling is consistent with descending motions at high latitudes, and it is speculated that it could provide an important additional drive for the general circulation.

Absolute line strengths and line positions for over 200 vibration-rotation transitions of PH 3 gas were measured at 295 K, using a tunable-diode laser spectrometer. The spectral range covered was from 2153.697 to 2210.566 cm −1 . Line strength measurements were reproducible to better than 5% on average, and the uncertainty in line positions was less than 0.002 cm −1 . Certain of the PH 3 lines were pressure-broadened with H 2 gas, and the pressure-broadening coefficients were determined.

A theoretical fit has been made to laboratory measurements of the 1-0 collisionally induced H2 absorption band over a temperature range of 100-273 K and for densities up to 22 amagats. Both the Birnbaum-Cohen and the MacTaggert-Hunt line shape profiles were used. In addition, an intermolecular potential of either a Lennard-Jones 6-12 or a Morse-spline-van der Waals has been used for each line shape. The best fit resulted in a chi-square of 5%. Line widths have also been derived as a function of temperature. The lifetimes of the states were calculated.

Measurements made at temperatures of 197, 233, and 294°K of the absolute intensities and self-broadening coefficients for the vibration-rotation lines of the 201III←000 band of the 12C16O2 molecule, are reported. From these measurements, values have been derived for the vibration-rotation interaction factor (FVR), the purely vibrational transition moment (|R(O)|), and the intensity (SBand). The results are: EVR(m) = 1+(2.2±0.7)×10−3 m+(5.6±1.6)×10×5m2, |R(0)| = (2.064±0.017)×10−3 debye, SBand = 21,329±69 cm−1 km−1 atm−1STP. The results for the self-broadening coefficients are presented in the text.

Corrected thermal net (upward minus downward flux) radiation data from four Pioneer Venus probes at latitudes of 4 deg and 60 deg N, and 27 deg and 31 deg S, are presented. Comparisons of these fluxes with radiative transfer calculations were interpreted in terms of cloud properties and the global distribution of water vapor in the lower atmosphere of Venus. The presence of an as yet undetected source of IR opacity is implied by the fluxes in the upper cloud range. It was also shown that beneath the clouds the fluxes at a given altitude increase with latitude, suggesting greater IR cooling below the clouds at high latitudes and a decrease of the water vapor mixing ratios toward the equator.

A Goody random band model with a Voigt line profile is used to calculate the band absorption of CFCB at various pressures at room and stratospheric (216 K) temperatures. Absorption coefficients and line spacings are computed.

Several photometric measurements of Venus made from the Pioneer Venus orbiter and probes indicate that solar near-ultraviolet radiation is being absorbed throughout much of the main cloud region, but little above the clouds or within the first one or two optical depths. Radiative transfer calculations were carried out to simulate both Pioneer Venus and ground-based data for a number of proposed cloud compositions. This comparison rules out models invoking nitrogen dioxide, meteoritic material, and volatile metals as the source of the ultraviolet absorption. Models involving either small ( approximately 1 micrometer) or large ( approximately 10 micrometers) sulfur particles have some serious difficulties, while ones invoking sulfur dioxide gas appear to be promising.

During the descent to the surface of Venus, the large probe infrared radiometer measured the net thermal radiative flux in several spectral bandpasses. Preliminary analysis has permitted us to estimate (i) the infrared extinction coefficient profile attributable to aerosols, with respect to their visible profile, in the upper atmosphere of Venus and (ii) the water vapor mixing ratio below the clouds. An indication of the composition of a multicomponent cloud is seen in the data from the spectral bandpass from 6 to 7 micrometers.

The 5 ν 1 absorption band of NH 3 is displayed from 6418 to 6550 A. The total band intensity has been measured: S B = 0.66 cm −1 m −1 amagat −1 . Line intensities and self-broadening coefficients have been measured for some of the prominent lines. Our line intensities are in good agreement with those of Rank et al . (1966) , but are about 2 times greater than those of Mason (1970) . The spectrum displayed was obtained photoelectrically at a pressure of 0.061 atm, and shows many more lines than the spectrum obtained by McBride and Nicholls (1972a) at a pressure of 0.39 atm. Therefore, our new measurements can provide the basis for making a more complete rotational analysis than those of McBride and Nicholls (1972a) . Since the total band absorption has previously been measured by others on moderate resolution photoelectric scans of the spectra of Jupiter and Saturn, we can use the band intensity to derive the NH 3 abundance in the atmospheres of these two planets. The NH 3 abundances in a single vertical path obtained by this method are about 10m amagat for Jupiter and 2m amagat for Saturn. These results are in agreement with previous results obtained from higher resolution photographic spectra.

We have analyzed the P6, P8, and P10 lines in the 0.7820 μm CO2 band of Venus using a scattering model. Our new results compare favorably with previous results from the 1.05 μm CO2 band. We considered nonabsorbing and absorbing clouds. We found that the anisotropic scattering mean free path for both models at the 0.2atm level is between 0.55 and 0.73km, a range close to the value of 1 km for terrestrial hazes. We used our scattering models to synthesize the 0.8226 μm H2O line, assuming that the clouds are composed of sulfuric acid drops, and found our nonabsorbing cloud required a sulfuric acid concentration of 82% by weight, while our thicker absorbing cloud required a concentration of 89%. A comparison of the variation of optical depth with height for our cloud models with the variation reported by Prinn (1973, Science 182, 1132–1134) showed that, within a factor of 2, the variation for Prinn's thinnest cloud agreed with ours. Whitehill and Hansen (1973, Icarus 20, 146–152) have recently confirmed the work of Regas et al. (1973a, J. Quant. Spectry. Radiative Transfer 13, 461–463) which showed that two cloud layers are not required to explain the CO2 phase variation of Venus. Prinn's recent photochemical study of sulfuric acid clouds further supports a single, continuous cloud layer in the line formation region instead of two cloud layers with an extensive clear region between. The single layer model appears more likely because the maximum particle density in Prinn's cloud occurs in the clear region between the two layers in the models of Hunt (1972, J. Quant. Spectry. Radiative Transfer 12, 405–419) and Carleton and Traub (1972, Bull. Amer. Astron. Soc. 4, 362.).

Quantitative measurements of intensities and half-widths were made for individual rotational lines of the atmospheric oxygen B band. The total band intensity, as derived from the line intensity measurements, is 40·8±0·6 cm −1 km −1 atm −1 STP. As had been previously found in this laboratory for the oxygen A band, the relative line intensities conform closely to the rotational distribution calculated by either Schlapp or by Watson. The line half-widths at half-intensity were determined for oxygen self-broadening for the P Q and P P branch lines and for a few R Q and R R branch lines near the band origin, and were found to vary from 0·064 cm −1 atm −1 at J ′ = 1 to 0·042 cm −1 atm −1 at J ′ = 25.

A theoretical fit has been made to our laboratory measurements of the 2-0 collisionally induced H2 absorption band for temperatures of 122 and 273.3 K and at a density of 20 amagats. A Lennard-Jones 6-12 intermolecular potential and a Birnbaum-Cohen line profile have been used. The fit resulted in a chi-square of 0.2%. Line widths have also been derived as a function of temperature. The lifetimes of the states have been calculated.

The absolute intensities of the 8-12 micron bands from Freon 11 (CFCl3) were measured at temperatures of 294 and 216 K. Intensities of the bands centered at 798, 847, 934, and 1082 per cm are all observed to depend on temperature. The temperature dependence for the 847 and 1082 per cm fundamental regions is attributed to underlying hot bands; for the nu2 + nu5 combination band (934 per cm), the observed temperature dependence is in close agreement with theoretical prediction. The implication of these results on atmospheric IR remote-sensing is briefly discussed.

Quantitative measurements of intensity and half-width have been made for over 30 lines in each of the C12O162 bands of the 1·6 μ tetrad. The total band intensities, derived from the line intensity measurements, for the (30°1)I, (30°1)II, (30°1)III, and (30°1)IV bands are 127, 1050, 1070, and 122 cm-1 km-1 atm-1 STP, respect ively. The observed rotational line intensity distribution of the (30°1)III band was found to depart slightly from the Boltzmann distribution. A satisfactory fit to the observed distribution was obtained by applying a weak vibration- rotation interaction. The widths of the lines of the (30°1)IV band are found to be 50 per cent larger than those of the other members of this tetrad.

The quantitative intensity of the weak CO2 triad in the 1 μ spectral region has been measured. Integrated R-branch intensities were obtained by using pressure broadening techniques with absorbing paths up to 4·8 km-atm. The R-branch intensities for the transitions 20°3«00°0, 12°3«00°0, and 04°3«00°0 are 1·27, 3·50, and 0·59 cm−1 km−1 atm−1 S.T.P., respectively. Intensities and half-widths of the J4 through J22 lines in the P-branch of the 12°3«00°0 transition have been determined.

Atmospheric oxygen A band individual rotational lines intensities and half widths measurements

An example is presented which demonstrates the importance of using physically realistic derivatives of the intermolecular potential when fitting pressure-induced spectra. The use of nonrealistic derivatives may mask second-order temperature effects in the theory. As the temperature decreases, the intermolecular potential may have an important angular dependence.

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.

Cytoplasmic and nuclear androgen receptors were quantitated in specimens of histologically normal and adenocarcinomatous human prostate and lymph node metastases of prostatic adenocarcinoma. Normal human pelvic lymph nodes did not have androgen receptors. One patient specimen did not have cytoplasmic androgen receptors, and 3 additional patient specimens showed predominant nuclear localization of androgen receptors. The remaining 88‰ (30 of 34 specimens) of the patient specimens showed either essentially equal distribution between the 2 compartments or predominant cytoplasmic localization of prostatic androgen receptors. Total androgen receptor content was related to epithelial cell content of prostate specimens composed of either glandular hyperplasia or mixed glandular and stromal hyperplasia. Some specimens of primary prostatic adenocarcinoma could be included in this group of tissues. However, prostate specimens principally composed of stromal hyperplasia could not be included. The mean androgen recep...

Ammonia red and green bands measured line positions, strengths and half widths applied to Jupiter atmospheric pressure determination

Because of the controversy over the value of the band strength for the nu-4 fundamental of CH4, equivalent widths of the R(0), R(1), and P(11, 11, F1) lines have been measured to compare with opposing views. The present measurements are consistent with the band strength of Ko and Varanasi (1977), who, on the basis of high-resolution line-strength measurements, propose an integrated band strength of 145 kaysers/(cm-am).

Recent measurements conducted from the Pioneer Venus probes and orbiter have provided a significantly improved definition of the solar net flux profile, the gaseous composition, temperature structure, and cloud properties of Venus' lower atmosphere. Using these data, we have carried out a series of one-dimensional radiative-convective equilibrium calculations to determine the viability of the greenhouse model of Venus' high surface temperature and to assess the chief contributors to the greenhouse effect. New sources of infrared opacity include the permitted transitions of SO2, CO, and HCl as well as opacity due to several pressure-induced transitions of CO2. We find that the observed surface temperature and lapse rate structure of the lower atmosphere can be reproduced quite closely with a greenhouse model that contains the water vapor abundance reported by the Venera spectrophotometer experiment. Thus the greenhouse effect can account for essentially all of Venus' high surface temperature. The prime sources of infrared opacity are, in order of importance, CO2, H2O, cloud particles, and SO2, with CO and HCl playing very minor roles.

Instruments flown on the Pioneer Venus orbiter and probes measured many of the properties of the atmosphere of Venus which control its thermal balance and support its high surface temperature. Estimates based on orbiter measurements place the effective radiating temperature of Venus at 228±5 K, corresponding to an emission of 153±13 W/m², and the bolometric Bond albedo at 0.80±0.02, corresponding to a solar energy absorption of 132±13 W/m². Uncertainties in these preliminary values are too large to interpret the flux difference as a true energy imbalance. A mode of submicron particles is suggested as an important source of thermal opacity near the cloud tops to explain the orbiter and probe thermal flux measurements. Comparison of the measured solar flux profile with thermal fluxes computed from the measured temperature structure and composition shows that the greenhouse mechanism explains essentially all of the 500 K difference between the surface and radiating temperatures of Venus. Precise comparison of the observed and computed value of this difference is hindered by uncertainties in the local variability of H_(2)O and in the thermal opacity of CO_2 and H_(2)O at high temperature and pressure. The directly measured thermal flux profiles at the small probe sites are surprisingly large and variable in the lower atmosphere. Observed zonal and meridional circulation are qualitatively as required to produce the observed uniformity of temperature structure. However, the present lack of quantitative estimates of the horizontal and vertical dynamical heat transports implied by these measurements is a significant gap in the understanding of the thermal balance of the atmosphere of Venus.

The model predictions were compared with the Pioneer Venus probes and orbiter to determine the composition of the UV absorbing materials. The simulations were carried out with radiative transfer codes which included spacecraft constraints on the aerosol and gas characteristics in the Venus atmosphere; gaseous SO2 (a source of opacity at the wavelengths below 0.32 microns), and a second absorber (which dominates above 0.32 microns) were required. The UV contrast variations are due to the optical depth changes in the upper haze layer producing brightness variations between equatorial and polar areas, and to differences in the depth over which the second UV absorber is depleted in the highest portion of the main clouds.

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.