scholarly journals Zodiacal Light - Scattered Fraunhofer Line Profiles

1996 ◽  
Vol 150 ◽  
pp. 337-340
Author(s):  
David Clarke

AbstractThe scattering function of Hong's successful model for the brightness variation with elongation, B(ε), of the Zodiacal Light has been used to calculate profiles of Doppler shifted Fraunhofer lines. Substantial line shape changes with ε are predicted with an indication of a bifurcation at ε < 30°, so offering an explanation for reported F corona observations.

1985 ◽  
Vol 85 ◽  
pp. 223-226
Author(s):  
K. Weiss-Wrana ◽  
R.H. Giese ◽  
R.H. Zerull

AbstractThe investigations of light scattering by larger meteoritic and terrestrial single grains (size range 20 μm to 120 μm ) demonstrate that the scattering properties of irregularly shaped dark opaque particles with very rough surfaces resemble the characteristic features of the empirical scattering function as derived from measurements of the zodiacal light. Purely transparent or translucent irregularly shaped particles show a quite different scattering behaviour. Furthermore irregular and multicomponent fluffy particles in the size range of a few microns were modelled by microwave analog measurements in order to explain positive and negative polarization of the light scattered by cometary dust grains.


Nature ◽  
1962 ◽  
Vol 193 (4817) ◽  
pp. 762-762 ◽  
Author(s):  
J. F. GRAINGER ◽  
J. RING

1983 ◽  
Vol 38 (1) ◽  
pp. 37-46 ◽  
Author(s):  
A. Piel ◽  
H. Richter

Abstract The line profiles of the overlapping helium lines 447.1 nm and 492.2 nm have been investigated in an improved plasma source of high purity at electron densities of 1 × 1021 m−3 and 3 × 1021 m−3 . The plasma parameters Ne, Te and T0 were determined carefully by independent diagnostics, which enables a critical comparison with existing theories (BCS II and MMM). We observed ion dynamic effects which considerably modify the line shape of the forbidden components. Our experiments extend the existing observations towards higher ion temperatures. Systematic trends observed earlier are critically discussed.


2013 ◽  
Vol 91 (11) ◽  
pp. 879-895 ◽  
Author(s):  
A.D. May ◽  
W.-K. Liu ◽  
F.R.W. McCourt ◽  
R. Ciuryło ◽  
J. Sanchez-Fortún Stoker ◽  
...  

An overview of the binary collision impact theory of spectral line shapes has been given to provide a unified statistical mechanical approach to line-shape theory, laser theory, nonlinear optics, and transport phenomena in dilute gases. The computation of spectral line profiles corresponding to those obtained from ultra-high-resolution spectral line-shape measurements requires numerical ab initio calculation of scattering amplitudes directly from the underlying dynamics of collisions between radiatively active molecules and their perturbers. The Wigner distribution function–density matrix is utilized to describe the kinetic theory of spectral line shapes and to discuss the various collisional processes that contribute to the kernel of kinetic equations. The influence of features of the potential energy surface on spectral parameters is also discussed, and the importance of comparing experimental line profiles directly with numerically computed line shapes obtained from reliable interaction potentials is emphasized. This contrasts sharply with the universal practice of comparing experimental line widths and shifts using some average or approximate theoretical scattering cross-sections and it contrasts sharply with fitting experimental profiles to some convenient analytical line-shape model; hence the phrase “a paradigm shift” in the title of this work.


1999 ◽  
Vol 82 (8) ◽  
pp. 1740-1743 ◽  
Author(s):  
D. Claesson ◽  
S.-Å. Lindgren ◽  
L. Walldén ◽  
T.-C. Chiang
Keyword(s):  

2000 ◽  
pp. 7-33 ◽  
Author(s):  
N. Stanic ◽  
L.C. Popovic ◽  
A. Kubicela ◽  
E. Bon

We present here the Akn 120 H? line profiles from 97 spectra observed from 1977 till 1990 at Crimean Astrophysical Observatory (Appendix 1). The H? line has been fitted with three broad and one narrow Gaussian throughout the whole considered period. The central broad components of the H? and a shelf cause the H? line shape variation. Three broad Gaussians may suggest the existence of three broad line regions in the central part of the Akn 120. Long-term H? line shape variations in spectra of this galaxy are discussed.


1992 ◽  
Vol T41 ◽  
pp. 259-264 ◽  
Author(s):  
L Calliari ◽  
M Sancrotti ◽  
L Duò ◽  
R Cosse ◽  
P Weightman ◽  
...  
Keyword(s):  

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