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91.
V. Banfi 《Celestial Mechanics and Dynamical Astronomy》1987,40(1):67-76
The containment property Goudas' surfaces has been studied in this paper. Physical implications of this property a consequently discussed. A general relationship is obtained, which connects the sizes of those surfaces, the magnetic moments of two stars and their mean motion. 相似文献
92.
93.
Quasi-steady high-temperature current sheets are an energy source during the main or hot phase of solar flares. Such sheets are shown to be stabilized with respect to the tearing instability by a small transverse component of magnetic field existing in the sheets. 相似文献
94.
Radio astronomy experiments designed to probe the interplanetary plasma close to the Sun have been carried out at the wavelength = 2.92 m using the occultation method. The experiments are based on a modification of the occultation method by which the sources, in this case quasars, are used to measure the radial dependence of the apparent source size, the scattering angle (R). The radial dependence of this source size (R) reveals that an anomalous enhancement in the scattering appears at radial distances from about 16 to 30 R
, which is associated with the solar wind transsonic region. It is shown by analysis of the theoretical equations that the radial profiles of both the source size (R) and the scintillation index m(R) are consistent in the near solar interplanetary medium (R 40 R
). Combining these two independent applications of the occultation method extends the range of the investigation and provides a powerful new diagnostic of the solar wind transsonic region. 相似文献
95.
Formulae containing the elements of the variational matrix are obtained which determine the linear isoenergetic stability parameters of three-dimensional periodic orbits of the general three-boy problem. This requires the numerical integration of the variational equations but produces the stability parameters with the effective accuracy of the numerical integration. The conditions for stability, criticality, and bifurcations are briefly examined and the stability determination procedure is tested in the determination of some three-dimensional periodic orbits of low inclination bifurcating from vertical-critical coplanar orbits. 相似文献
96.
An analysis of the effects of the mass transfer on the unsteady free-convection flow of a viscous incompressible fluid, past an impulsively started infinite porous vertical limiting surface with heat sources is presented, when the free-stream velocity and the suction velocity, are oscillating in the time about constant mean values. Approximate solutions for the coupled nonlinear equations are derived for the mean velocity, the mean temperature, the mean skin-friction, and the mean rate of heat transfer. All the above quantities are shown graphically followed, by a discussion. 相似文献
97.
This paper is devoted to Force-Free Electromagnetic Oscillations in a constant magnetic field. A correction is made in the derivation of the basic equation. The paper confirms the predicted spectrum of frequencies, namely
n
=
o
(n + 1)1/2;n = 0, 1, 2, .... In addition it is suggested that hybrid frequency
n
= (
n
2
+
H
2
)1/2 should be found in observational data. 相似文献
98.
T. Landscheidt 《Solar physics》1986,107(1):195-199
The Blackman-Tukey power spectrum of flare generated X-ray bursts X1 observed from 1970 to 1982 by satellite instrumentation (SOLRAD/SMS/GOES) shows prominent peaks at 156, 4.8, 2.8, and 1.1 months. According to a statistical test of the significance of the deviation of these peaks from Markov red noise, the peaks at 2.8 and 1.1 months are significant at the 99% confidence level while the peak at 4.8 months reaches the 95% level. A replication by means of the maximum entropy spectral analysis (MEM) yields the same prominent peaks at the same frequencies. 相似文献
99.
The abundances of light elements (deuterium, helium and lithium) are calculated in unconventional cosmologies in which these elements are produced by interaction of fast -particles ejected by massive pregalactic stars with a purely hydrogenous cosmological substrate. The number density and energetics of such stars needed for suitable production of light elements are estimated. It is shown that the models always lead to overproduction of lithium. The intensity of ultraviolet, X-ray, and -ray emission caused by explosions of pregalactic massive stars is calculated. The distortions of cosmic background radiation by Compton losses of electrons heated by explosive stars are also calculated. 相似文献
100.
A simple self-consistent model of a high-temperature turbulent current sheet (HTCS) is considered. The anomalous character of plasma conductivity in a sheet is assumed to be due to gradient instabilities. The possibility of a low threshold of their excitation is demonstrated by an example of temperature-drift instability.Application of the HTCS model to the hot or main phase of a solar flare is discussed. The model consistently explains many observed properties of this phase. 相似文献