Showing papers in "Journal of Atmospheric and Solar-Terrestrial Physics in 1972"

TL;DR: In this paper, the effects of the neutral-air winds on the ionospheric F2-layer are considered in some detail, starting from a discussion of the forces acting on the air, the equations of motion are set up and solved.

TL;DR: In this paper, an improved and simplified analytical characterization of differential cross sections leading to secondary electrons following bombardment at a fixed primary electron energy is presented, which can describe phenomenologically the falloff in the production of secondary electrons at low and at high energies more accurately.

TL;DR: In this article, a number of analytic forms are presented which have been used to represent electron impact excitation cross sections all the way from threshold to the high energy domain where they join approximately to the results of the Born-Bethe approximation.

TL;DR: In this article, the authors measured electron concentrations in the lower ionosphere (55-95 km altitude) above Wallops Island, Virginia, by 10 Nike Apache rockets at solar zenith angles of about 60°.

TL;DR: In this article, the emission of bremsstrahlung by electrons in the upper atmosphere and the penetration of this radiation to atmospheric depths of 3 to 10 g/sq cm, where it can be measured by balloon-borne detectors.

TL;DR: In this article, positive ion composition measurements in the D- and lower E-regions were performed on three rocket flights during the November 1966 solar eclipse program conducted at Cassino, Brazil.

TL;DR: In this article, the authors examined the nature and magnitude of the decrease as a function of flare flux, developed model recombination coefficient profiles for different flare conditions, and then offer a theory of how these decreases can occur.

TL;DR: In this article, the frequency spectra of signals incoherently scattered by ionospheric electrons often reveal slight shifts caused by macroscopic motions of the ions, and suggest means by which the utility of the incoherent scatter technique could be exploited further.

TL;DR: In this article, a full wave calculation of gravity wave propagation in a realistic thermospheric model, including the effects of height dependent temperature and winds, of Coriolis force, viscosity, thermal conduction, and ion drag, is presented.

TL;DR: In this article, the hydrodynamic solutions of the polar wind can be fitted to the kinetic solutions applicable to the upper ionospheric polar regions where the Coulomb collisions are negligible.

TL;DR: In this article, a model of the ionospheric plasma is described by means of the momentum and continuity equations for O +, He +, H + and the energy equations for T e and T i.

TL;DR: In this paper, the effect of the ambipolar plasma diffusion from the incoherent scatter measurements of ion density and electron and ion temperatures was evaluated for various F -region altitudes after evaluating the effect.

TL;DR: In this article, time-dependent solutions of the diffusion and continuity equations are used to examine the diurnal variations of constituents in an oxygen-hydrogen atmosphere, and account has been taken of recent revisions in solar-flux data, predissociation of molecular oxygen in the Schumann-Runge bands, and experimental data on the height variation of eddy diffusion coefficient.

TL;DR: In this article, photoionization and photoabsorption cross sections for N 2, O 2 and O are presented in a form useful for calculation of solar EUV absorption and photoelectron production.

TL;DR: The relativistic electron precipitation (REP) events of August 11 and 25, 1967 were investigated in this article with regard to the energy spectra of trapped and precipitated electrons.

TL;DR: In this article, a rocket technique for measuring electron density and collision frequency in the lower ionosphere is described, where absolute values of electron density were determined by a radio propagation experiment, and detailed height variations were measured with a Langmuir probe.

TL;DR: In this article, a three-dimensional model of the thermosphere dynamics is developed in terms of the eigenfunctions of the atmospheric system, and a three dimensional model for the external heat inputs like solar XUV-radiation and corpuscular heating during geomagnetic storms is derived.

TL;DR: In this paper, observations of very low frequency radio signals were made in Newfoundland during the solar eclipse of 7 March 1970, where the ionospheric reflector height varied from 69 km at the start of the eclipse to 76 km at maximum totality.

TL;DR: The importance of allowing for the variation in the absorption cross-section of oxygen across the width of the Lyman-α line profile is discussed in this paper, and an allowance has been made for the absorption produced by other atmospheric constituents.

TL;DR: Balloon recordings of bremsstrahlung X-raya from precipitating electrons are presented, showing impulsive Xray events just at the onset of bay activity as well as weaker and smoother electron precipitation before the bay, the latter apparently being connected with a growth phase of the same substorm as mentioned in this paper.

TL;DR: In this paper, a sounding-rocket payload, consisting of an assembly of extreme ultraviolet (EUV) spectrometers and plasma probes designed for simultaneous measurement of related ionospheric parameters, is described, and results obtained from a flight of this payload on a sun-pointing Skylark sounding rocket at Woomera, S. Australia (31°S, 137°E) on 3 April 1969 are presented in detail.

TL;DR: In this paper, a correlation analysis of three-station observations of satellite amplitude scintillations, recorded at London, Canada during the summer of 1968, has been interpreted to give information on the height, size and shape of the ionospheric irregularities.

TL;DR: In this paper, it is concluded that the true ambient composition and concentration of minor neutral constituents and positive and negative ions must be accurately measured before meaningful theoretical model studies can proceed, and that the positive-ion chemistry in the disturbed high-latitude D-region appears to be understood better than that in the undisturbed Dregion.

TL;DR: In this paper, the solar eclipse of Mar. 7, 1970, with photometers sensitive to narrow bands of radiation at Lyman-alpha (1216 A) and at 2600 A included in the payloads of four Nike Apache rockets flown before and during the eclipse.

TL;DR: In this paper, an abrupt onset of scintillation on 40-MHz beacon satellite records occurs within the invariant latitude range 36-63° along the New Zealand meridian.

TL;DR: In this article, the a.c. Langmuir probe experiment of the satellite ESRO-1A measured electron temperatures in the topside ionosphere for a 6-month period centred on northern winter, and near the sunspot maximum.

TL;DR: In this article, it was observed that recombination-like electron loss coefficients measured during the March 1970 eclipse coincide with those from the November 1966 eclipse and range from 2 x 10 to the minus 7th power cu cm/sec at Z sub zero + 6 km to 0.00005 cu cm /sec at 0.008 per sec.

TL;DR: In this paper, electron and positive ion densities and their relationship to ionization sources in the equatorial D region were investigated, and the relationship between the two densities was investigated.

TL;DR: In this article, the first two zonal harmonics, zonal wave numbers 1 and 2, were correlated with the corresponding harmonics of the atmospheric pressure fields for the stratosphere, and the observed relationship was tentatively explained as due to approximately vertical planetary-scale disturbances of the temperature field which are associated with the fluctuations of the planetary scale waves in the constant pressure surfaces.

TL;DR: The Sudden Ionospheric Disturbances (SID) produced in the Earth's ionosphere by enhanced solar radiation during solar flares are examined in the light of recent information on flare X-ray emission as mentioned in this paper.