空间科学学报

1985 Vol. 5, No. 2

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Non-axisymmetric Magnetostatic Equilibrium in Cylindrical Coordinates and Its Application to Sunspots

Hu You-qiu, Xu Wei-dong

1985, 5(2): 75-83. doi: 10.11728/cjss1985.02.075

Abstract(1871) PDF 512KB(1283)

Abstract:
The present paper describes a general solution to the three-dimensional, two-con-ponent magnetostaitic equations in cylindrical coordinates, assuming the total pressure (sum of gas pressure and magnetic pressure) is a function of the altitude only. By adjusting the two arbitrary functions appearing in the general solution one may produce various patieular solutions which are not subjected to any limitation of perturbation conditions while applied to solar phenomena. Moreover, it is found that a particular solution as to qualitatively elucidate the asymmetry of sunspots in shape in addition to the filamentary structure in sunspots.

Some Properties of X-ray Selected Quasars

Liu Ru-liang, Yang Hao-shou

1985, 5(2): 84-91. doi: 10.11728/cjss1985.02.084

Abstract(2179) PDF 557KB(1213)

Abstract:
Statistical analysis for 109 X-ray selected quasars as well as 114 radio and optically selected quasars ds carried out in this paper. On the histograms of their redshift, optical luminosity and average optical X-ray spectral index, it is found that X-ray selected quasars are distributed at the low ends of plots of these parameters. On the plot of the monochromatic X-ray luminosity against the monochromatic optical luminosity l0 for all samples, most of the X-ray selected quasars are situated in'optically-faint regions of low luminosity. If we take lglo=31.2erg/s·Hz as a line of demarcation, and divide the optical luminosity into optically-bright and optically-faint regions, it is found that the radio and optically selected quasars have a slope of b=0.64 in the optically-bright region on this plot, and 6=0.95 in the optically-faint region, while the value of b of the X-ray selected quasars is only 0.78, thus implying that they may be a subtype of quasar phenomenon. Finally the factors affecting b are discussed briefly.

The Mechanism for Accelerating and Heating the High Speed Solar Wind Between 0.3AU and 1AU

Zheng Zi-rao, Zhao Xue-pu

1985, 5(2): 92-100. doi: 10.11728/cjss1985.02.092

Abstract(2203) PDF 578KB(732)

Abstract:
The momentum and energy equations for the high speed solar wind, which include all kinds of possible acceleration and heating processes, are examined simultaneously by using Helios'observations of protons and MHDfluctuations in the high speed wind ranging from 1 AUto 0.3 AU. The estimation shows that the viscous effect can not be represented by the classical expression of viscosity, which is derived from the collision-dominated plasma. It is suggested that in the region (at least) between 0.3AU and 1AUthe high speed wind acceleration by thermal pressure gradients is comparaline to that by Alfven wave pressure gradient, the acceleration by the Lorentz force of the background field is neglegible. As for the deceleration and heating, others are needed to include in addition to the solar gravity and Alfven wave heating. The function of viscosity is just both decelerating and heating, therefore the reexamination of viscous effect in the high speed wind appears to be worthwhile.

The Influence of Shearing Neutral Winds on the Two Stream Instability in the Equatorial Electrojet

Tu Chuan-yi

1985, 5(2): 101-107. doi: 10.11728/cjss1985.02.101

Abstract(1857) PDF 441KB(888)

Abstract:
The influence of the vertical current driven by some shearing neutral winds an the dispertion relation, the growth rate and the saturated turbulence level of the two-stream instability in the equatorial electrojet is discussed. For j_⊥～2×10^-7A/m², the influence is obvious and can be significant when the driven electric field approches the critical value of the instability. It is shown that the vertical current driven by semidiurnal tidal winds is one of the possible reasons of the high turbulence level of type "H" echoes observed during the counter-electrojet.

The F-region Behaviour over the Pacific Area During the Typical Solstitial Geomagneto-ionospheric Storms

Huang Tian-xi

1985, 5(2): 108-116. doi: 10.11728/cjss1985.02.108

Abstract(2214) PDF 641KB(762)

Abstract:
In this paper, features of the total electron content and F-region of the ionosphere over the Pacific area during the typical storms are analysed on the basis of published data and some new results are presented. It is suggested that the ionospheric storm characterized by TECreaches quite distinct degree while the main phase of magnetic storm appears. The behaviour of the ionosphere, mainly the F-region, is dominated strongly by the complex relation of longitude (storm commencement), latitude, geomagnetic configuration and season (the Southern or Northern Hemisphere). It is necessary to consider the growth and decline of TECaccording to the ionization increase rate (magnetic field line retrenchment), depletion rate (loss coefficient rise) as well as transportation rate (ionization transfer between geomagnetic conpugate points and the crest-trough movement). Amore reasonable suggestion with regard to the ionospheric storm division and the phase reverse is proposed.

Seasonal Variations of Atmospheric Ionization Rates in Low and Middle Atmosphere Produced by the Seasonal Variations of Atmospheric Densities

Zhuang Hong-chun

1985, 5(2): 117-122. doi: 10.11728/cjss1985.02.117

Abstract(2233) PDF 414KB(675)

Abstract:
In this paper calculations of the seasonal variation of atmospheric ionization rate in low and middle atmosphere produced by the seasonal variation of atmospheric density in CIRA 1972 are conducted. Cosmic ray ionization source functions are used to numerically calculate the ionization rate in the low and middle atmosphere of the whole globe. The results show that the order of the amplitudes of seasonal functions of the atmospheric ionization rate at altitudes below 70 km are several tens percent. Below the altitude of ionization peak (about 15km), the amplitude as about 10%, the higher the altitudes, the larger the amplitudes, and it will reach 35% at 70 km. Above 20 km the seasonal variations of ionization rates are glossly proportional to that of atmospheric densities, being larger in summer than in winter. Below 20 km, the situation is more complicated.

The Origin of Galactic Protons and the Spectrum of Primary Protons

Xu Chun-xian

1985, 5(2): 123-128. doi: 10.11728/cjss1985.02.123

Abstract(2244) PDF 438KB(1094)

Abstract:
By using an isotropic diffusion statistic model with explosive discrete sources in an infinite galaxy, the transport equation for galactic cosmic ray proton is investigated. The non-steady state solution of the equation is obtained utilizing the very recent data of cross-section of P-Pinteraction and a reasonable diffusion coefficient. Then some features of the solution and the possible contribution to the proton spectrum from lots of this kind of sources are discussed. The expected spectrum can account for the experimental data quite well.

Effects of Geomagnetic Field Models on Whistler-mode Ray Tracing at Low Latitude

Liu Shao-liang, Gao Yu

1985, 5(2): 129-134. doi: 10.11728/cjss1985.02.129

Abstract(1904) PDF 367KB(677)

Abstract:
In view of the large difference between the real geomagnetic field and the dipolar model field at low latitudes, ray tracing for whistler-mode wave propagation has been performed with IGRF (n=6). It is found that there are two narrow nonducted propagation outlets of whistler-mode wave at about 9° Nand 12°N, their starting regions are in the area of storm activity. The cutoff latitude of outlet of whistler-mode wave is at 8°N-9°N. The results of this computation can be used satisfactorily to explain the fact that the dispersion of whistler at low latitude is in positive correlation with f₀/F₂.

The Outer Ionospheric Effect of the Solar Eclipse on 31 July 1981 at Mohe

He You-wen, Huang Tian-qiao, Zhu Mu-qiu, Su Shi-hua

1985, 5(2): 135-143. doi: 10.11728/cjss1985.02.135

Abstract(1994) PDF 584KB(878)

Abstract:
In this paper the whistler data received at Mohe (Magnetic Longitude 190°17"E, Magnetic Latitude 42°18"N) and the simultaneously observed ionospheric data are used, along with the assumption that the electron density distributions at Nonth and South hemispheres are necessarilly symmetric, to study the effects of solar eclipse of 31 July, 1981 on the whistler dispersion. The electron density profile along magnetic line of force, electron contect of magnetic flux and equivalence scale height at Mohe during the solar eclipse are also determined. In addition, the outer ionospheric effect of the solar eclipse are also discussed

The Electric Field Distribution in High-latitude Ionosphere Based on the Field-aligned Currents

Guo You-min, Shen Chang-shou, Zi Min-yun

1985, 5(2): 144-154. doi: 10.11728/cjss1985.02.144

Abstract(2036) PDF 550KB(1113)

Abstract:
This paper is based on the TRIADobserved statistical diurnal Variation of the field-aligned currents. The analytical solution of the electric potential in high-latitude both under homogeneous and inhomogeneous conductivities are deduced respectively by using the simple model method and the Fourier series expansion of the observed diurnal distribution of the fieldjaligned currents. The pattern of the electric potential based on TEIADobservations and the effects of the conductivities under such conditions are discussed through the model calculation. The results show that the'shielding'of the E-fie-Ids are caused by the region 2 field-aligned currents in our case, and under the distribution of the field-aligned currents used here the enhancement of Hall conductivities in the auroral zone may even weaken the'shielding'. During |AL|≥100r, the combined efect of the two rigions of field-aligned currents may produce a 8?rotation of the convection cells, however, the further rotation of the whole pattern is the results of the enhancement of Hall conductivities in auroral zone, and the enhancement of Pederson conductivities has no effect on this rotation. It is also .shown, even without the day-night gradient of the conductivities the two eovection cells can be unsymmetrical, this unsymmetry is caused by the complicated diurnal variation of the two regions of the field-aligned currents.The structure of the oacuilated E-field based on TEIADmeasurments is in agreement reasonably with the observed E-field pattern such as by STAREand by many other experiments. The effect of the three sheet pattern of field-aligned currents pre-midnight and of the cusp current around noon are not taken into account in this work.