Results 251 to 260 of about 5,737,181 (292)

An infrared Schlieren interferometer for measuring electron density profiles

Plasma Physics, 1972
In rotationally symmetric plasmas one can determine the electron density profiles from refractive index effects, preferably by using infrared radiation. In this report the diagnostic value of schlieren techniques is compared to that of interferometry. As a very efficient diagnostic setup, a combined schlieren interferometer is introduced, which makes ...
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A study on the cosmic electron density profile

2002
Abstract This paper shows a simulation process of retrieving ionospheric electron density from the Global Positioning System/Meteorology (GPS/MET) to examine the accuracy of the retrieval procedure for the COSMIC project 3 during solar minimum and maximum periods. Results show that the error of the maximum electron density ( NmF 2 ) is under 25%,
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Model electron density profiles for the lower ionosphere

Journal of Atmospheric and Terrestrial Physics, 1969
The Sen-Wyller generalised magneto-ionic theory has been applied to experimental data on ionospheric absorption and virtual heights at frequencies near 2 MHz and it is shown that in the lower ionosphere, over the height range 65–95 km, the electron density distribution can be represented by a function of the form N(h) = N(h0)ea1(h−h0)+a2(h−h02 ...
W.J.G. Beynon, S. Rangaswamy
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Variational approximation of the electronic density profile at the surface of jellium

Physical Review B, 1988
A variational method not restricted to a given class of trial functions is proposed for obtaining the electron density minimizing the energy functional E[n] directly in the surface region of jellium. Remaining within the local-density approximation, the kinetic-energy contribution is considered as proposed by Kirzhnits.
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Ionospheric Electron Density Profile and Related Studies.

1981
Abstract : We have studied photo-ionization of the neutral gas by photons in the extreme ultraviolet (EUV) region of the solar spectrum along with the various particle-particle collisional processes that determine the energy dependence of the photo-electron flux.
Ed R. Smith, Tien S. Chang, Bamandas Basu   +2 more
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Electron density profile analysis at low latitudes

Advances in Space Research, 1988
Abstract The shape of the electron density profile obtained from daytime hours centered at noon composed ionograms at three low modifed dip ionospheric stations (Tucuman: −22,7; San Juan: −29,1; Buenos Aires: −32,24) was investigated. The profiles were divided in sections defined by the following points: the electron density corresponding to foE (NE),
S.M. Radicella, M.Mosert de González
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Erratum: Evaluation of electron density profiles in plasmas from integrated measurements

Journal of Applied Physics, 1979
Obtaining electron density profiles from integrated measurements (e.g., those made with a multichannel interferometer) in the case of asymmetrical plasma distributions often entails serious difficulties. Here we describe a method applicable when the profiles are shifted along the equatorial plane and also when the relation between phase shift and ...
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Plasmaspheric extension of topside electron density profiles

Advances in Space Research, 2002
Abstract Topside electron density profiles measured onboard ISIS-1 and ISIS-2 (1969 to 1980) and IK—19 (1979 to 1982) are extended through the plasmasphere using Chasovitin's (1999) model describing the plasma density between the peak of the ionosphere and the plasmapause.
Tamara L. Gulyaeva, Xueqin Huang, Bodo W. Reinisch   +2 more
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Electron density profiles in the ionosphere during the I.G.Y.

Journal of Geophysical Research, 1958
In many parts of the world during the last 20 years, regular measurements have been made of the maximum electron density (Nm) and the approximate true height (hm) of the various layers in the ionosphere. Both these parameters can be obtained fairly easily from the h′(ƒ) curves (ionograms) which are produced by automatic pulse-sounding equipment and ...
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Ionospheric electron density profiles at sunrise-sunset

Advances in Space Research, 1985
Abstract In order to improve its representation of the dependence on time and space of the ionospheric parameters, the International Reference Ionosphere ought to take account of realistic sunrise and sunset conditions in the upper atmosphere. Such input is needed for quite a few parameters for which only day and night values were taken as input in ...
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