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Spectral line formation by noncoherent photon scattering predicted theoretically for plane parallel medium of finite optical thickness, emphasizing Doppler broadening
Spectral line shapes broadened by electron impacts, taking into account contribution of radiation produced by perturbing electrons
Spectral line formation, assuming frequency redistribution for plane parallel stellar atmosphere containing nonuniform distribution of internal emission sources
Moment analysis of atomic spectral lines of Cs-Ar and Cs-He systems, using adiabatic approximation
The theory of the formation of spectral lines in a cloudy planetary atmosphere is studied in detail. It is shown that models based upon homogeneous, isotropically scattering atmospheres cannot be used to reproduce observed spectroscopic features of phase effect and the shape of spectral lines for weak and strong bands. The theory must, therefore, be developed using an inhomogeneous (gravitational) model of a planetary atmosphere, accurately incorporating all the physical processes of radiative transfer. Such a model of the lower Venus atmosphere, consistent with our present knowledge, is constructed. The results discussed in this article demonstrate the effects of the parameters that describe the atmospheric model on the spectroscopic features of spectral line profile and phase effect, at visible and near infrared wavelengths. This information enables us to develop a comprehensive theory of line formation in a Venus atmosphere.
Electron density measurement from atomic spectral line widths and shifts in cesium plasma electric discharge
Plasma radiation analyzed by spectral line broadening theory as relaxation of excited atom, noting frequency dependent width and shift operators
Doppler effect induced small spectral line shifts measured by modified duochromator in MPD arc jet
Ion charge determination from emitting spectral lines using beam foil light source technique
Spectral lines Doppler broadening reduction in spectroscopy using foil and gas excited accelerator beams as light sources
Index of refraction in neighborhood of stark broadened spectral line calculated by using relation between absorption coefficient and refractive index
Absorption oscillator strengths of spectral lines from medium and light elements
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.
Stark broadening of spectral lines in argon plasma and need to include Debye shielding effects
Ion charge identification for spectral lines in nitrogen by beam foil light source technique
Power spectral density analysis using Burg's maximum entropy method (MEM) was applied to the geomagnetic dipole field and its rate of change for the years 1901-1969. Both spectra indicate relative maxima at 0.015 cycle/yr and its harmonics. These maxima correspond approximately to 66-, 33-, 22-, 17-, 13-, 11-, and 9-year spectral lines. The application of the same analysis techniques to the length of day (l.o.d.) fluctuations for the period 1865-1961 reveals similar spectral characteristics. The existence of the common spectral peaks with periods of 66 and 33 years in the l.o.d. fluctuations and the geomagnetic dipole field is clearly established. The existence of the higher harmonics is somewhat uncertain because of the line-splitting problem in the MEM spectral analysis. It is suggested that the spectral line similarity in the l.o.d. fluctuations and the dipole field variations is related to the motion within the earth's fluid core during the past 100 years.
This viewgraph presentation reviews the requirements for improved coherent detector arrays for use in continuum and spectral line applications. With detectors approaching fundamental limits, large arrays offer the only path to sensitivity improvement. Monolithic Microwave Integrated Circuit (MMIC) technology offers a straightforward path to massive focal plane millimeter wave arrays: The technology will readily support continuum imagers, polarimeters and spectral line receivers from 30-110 GHz. Science programs, particularly large field blind surveys will benefit from simultaneous observations of hundreds or thousands of pixels 1000 element array is competitive with a cost less than $2M.