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101.
The thermal balance of the plasma in the night-time mid-latitude F2-region is examined using solutions of the steady-state O+ and electron heat balance equations. The required concentrations and field-aligned velocities are obtained from a simultaneous solution of the time-dependent O+ continuity and momentum equations.The results demonstrate the systematic trend for the O+ temperature to be 10–20 K greater than the electron temperature during the night at around 300 km, as observed at St. Santin by Bauer and Mazaudier. It is shown that frictional heating between the O+ and neutral gases is the cause of the O+ temperature being greater than the electron temperature; the greater the importance of frictional heating in the thermal balance the greater is the difference in the O+ and electron temperatures. A study is made of the roles played in the thermal balance of the plasma by the thermal conductivity of the O+ and electron gases; collisional heat transfer between O+ electrons and neutrals; frictional heating between the O+ and neutral gases; and advection and convection due to field-aligned O+ and electron motions. The results of the study show that, at around 300 km, electron cooling by excitation of the fine structure of the ground state of atomic oxygen plays a major role in the thermal balance of the electrons and, since the temperature of the ions is little affected by this electron cooling process, in determining the difference between the ion and electron temperatures. 相似文献
102.
A.B. Shvartsburg V.G. Korobeinikov M.G. Deminov A.V. Razmadze 《Planetary and Space Science》1979,27(2):159-163
The non-linear stationary temperature waves (domains) is analysed. The exact analytical solutions of the non-linear equation of the heat conductivity determine the region of existence of such domains and the critical values of plasma parameters, correspond to the increase of the periodical temperature profiles in the plasma. A stationary source of heating (photo-electrons or electric fields) may stimulate the existence of domains, when the power of the source reaches a critical value. Conditions in the F-region of the ionosphere near the equator favour the increase of the domains. 相似文献
103.
We present out methods of measurement and reduction of high-dispersion photographic spectra of Venus. Our preliminary results are consistent with slow direct or no rotation at the level we sample, and disagree strongly with a 4-day retrograde rotation. A serious systematic error, which affects much published work, is due to blending of solar lines in the sky with those reflected from the planet. This always tends to produce a spurious retrograde “rotation.” Only data obtained in a dark sky, or daytime observations from which the sky lines have been accurately subtracted, can be relied upon. All such data give low wind speeds. 相似文献
104.
Phase curves for the CO2 bands at 7883, 7820, and 8689 Å are presented. While the weaker bands at 7820 and 7883 Å show a definite “inverse phase effect,” the band at 8689 Å shows a more normal phase curve; it also exhibited much larger day-to-day variations in the CO2 abundance near superior conjunction in 1971. Because the variation of the phase curves with band strength is comparable to temporal variations on Venus, simultaneous observations of strong and weak bands are still needed to determine the dependence on band strength accurately. 相似文献
105.
The ionospheric plasma density on magnetic field lines threading the Jovian rings which are located inside ~1.8 RJ on the jovigraphic equatorial plane, is calculated by using a rotating ion exosphere model. It is found that the bulk of the ionospheric particles on these field lines are on ballistic trajectories. On field lines approximately symmetric with respect to the jovigraphic equator, the ring, which to a first approximation would absorb the population of trapped particles, consequently has little effect. On field lines which are made asymmetric by the higher-order multipoles of Jupiter's field and the tilt of the dipole axis, the rings may have a significant effect. It is suggested that better definition of the rings' atmospheric and ionospheric properties is required to model these localized effects. If the rings are found to be an important plasma source for the inner magnetosphere, the present exospheric model will have to be revised. 相似文献
106.
The Infrared Astronomical Satellite (IRAS) program will produce an extremely sensitive all-sky survey over the wavelength region 8 to 120 μm when the mission is flown in 1982. These data will provide a novel opportunity to detect planetary-sized objects having masses <0.08M⊙ or near our solar system. The improved detection limit of the IRAS will greatly increase the volume of space searched for such objects as compared with previous optical and infrared studies. 相似文献
107.
108.
Green's Theorem is developed for the spherically-symmetric steady-state cosmic-ray equation of transport in interplanetary space. By means of it the momentum distribution functionF
o(r,p), (r=heliocentric distance,p=momentum) can be determined in a regionr
arrbwhen a source is specified throughout the region and the momentum spectrum is specified on the boundaries atr
a
andr
b
. Evaluation requires a knowledge of the Green's function which corresponds to the solution for monoenergetic particles released at heliocentric radiusr
o
, Examples of Green's functions are given for the caser
a
=0,r
b
= and derived for the cases of finiter
a
andr
b
. The diffusion coefficient is assumed of the form = o(p)r
b
. The treatment systematizes the development of all analytic solutions for steady-state solar and galactic cosmic-ray propagation and previous solutions form a subset of the present solutions. 相似文献
109.
In the present paper, H-evolutive curves of chromospheric events are compared with flux evolutive curves of X-ray events observed at the same time in different spectral regions. A correspondence between the emissions E(I
H/I
chr)'s at higher and higher H-intensity levels, and the X-ray fluxes F()'s in harder and harder -ranges is shown. Further, the present observations seem to indicate the existence of a single triggering mechanism during the flash-phase of a flare. It is also shown that these results may be in agreement with Brown's model for chromospheric flares. 相似文献
110.
C. D'uston J. M. Bosqued F. Cambou V. V. Temny G. N. Zastenker O. L. Vaisberg E. G. Eroshenko 《Solar physics》1977,51(1):217-229
Solar wind and interplanetary magnetic field data were obtained by the PROGNOZ 1 and PROGNOZ 2 satellites during the period following the August 4, 1972 (0621 UT) solar flare. A thermalized plasma was recorded one hour after the shock followed two hours later by the plasma piston with a bulk velocity higher than 1700 km s-1. The comparison between the PROGNOZ and PIONEER 9 solar wind data shows an attenuation of the plasma properties with the deflection from the flare's meridian. 相似文献