1984 Vol. 4, No. 2

Display Method:
A Possible Mechanism of Solar Surges
Ding Jiu-ping, Xu Ao-ao
1984, 4(2): 89-95. doi: 10.11728/cjss1984.02.089
Abstract(1312) PDF 514KB(806)
Abstract:
It is synthesized that the principle observational features of solar surges, especially the magnetic features within the active region of surges. Using the plasma dynamical pinch theory and Petschek's mechanism, we present a possible mechanism of solar surges, namelya impulsive magnetic flux emergence in the active region--the periodical dynamical pinchof the plasma--the fast reconnection of the magnetic force lines--the ejection of surgeplasma. This mechanism successfully explains the periodicity of the surge ejection as well as the other main physical properties of solar surges.
Possibility of Triggering the Geomagnetic Disturbances by the IMF Northward Bz Component
Wu Lei, Song Xiao-ting
1984, 4(2): 96-104. doi: 10.11728/cjss1984.02.096
Abstract(1386) PDF 609KB(896)
Abstract:
The possibility of triggering the geomagnetic disturbances by the northward Bz component of the IMF is discussed using some typical events and statistical analyses. The coupling coefficient of the IEF Ey component to the large scale magnetospheric convection electric field is given. The response of the magnetosphere to the solar wind effects is analysed from the coupling equation of these two fields. The results show that the magnetosphere does not act as the half-wave rectifier to the solar wind effects, hence the classical recon-nection scheme of the magnetosphere is proposed to be somewhat modified.
Kelvin-helmholtz Instability and MHD Surface Waves on Saturn's Magnetopause
Pu Zu-yin, M. G. Kivelson
1984, 4(2): 105-111. doi: 10.11728/cjss1984.02.105
Abstract(1452) PDF 451KB(594)
Abstract:
The surface waves on Saturn's magnetopause are studied by examining the Kelvin-Hel-mholtz (K-H) instability at the interface between the magnetosheath and the magnetosp-here. It is demonstrated that the relative motion between corotating magnetospheric plasma and flowing magnetosheath plasma can provide free energy to generate the K-Hinstability at the magnetopause. On the afternoon side, the closer to the subsolar point, the more unstable is the magnetopause; and the instability conditions are satisfied most easily in the morning region. Using the MHD approximation and for parameters selected to represent the Voyager-1 inbound magnetopause crossing at Saturn, the wave characteristics which are in good agreement with the corresponding estimated values of observations reported by Lep-ping et al. (1981) is obtained.
A Simplified Model of the Magnetopause and the Lower-hybrid-drift Instability
Guan Jing, Yin Run-jie, Zhao Kai-hua, Tu Chuan-yi
1984, 4(2): 112-125. doi: 10.11728/cjss1984.02.112
Abstract(1351) PDF 820KB(848)
Abstract:
The paper discusses the lower-hybrid-drift instability in magnetopause from the simplified Lee-Kan distribution function. The results are compared with those obtained by the drift Maxwell distribution function. The saturated amplitude of the electric field perturbation is evaluated by current relaxation. It is consistent with the data observed-5mV/m.
The Dynamic Characteristics of Sequential Es in the Ionosphere
Li Zan-ju
1984, 4(2): 126-134. doi: 10.11728/cjss1984.02.126
Abstract(1382) PDF 595KB(941)
Abstract:
In this paper, the phenomenon Ess appearing in the daytime ionograms at Wuchang station (114°21.5'E,30°32.7'N) during the period 1964-1973 is analysed. It is discovered that the characteristics of this daytime phenomenon Ess are very similar to those of the nighttime phenomenon Em called '"nighttime thick-layer of motion". It is found that: (1) the heights of both Ess-layer and Em-layer descend gradually and their thickness become rather thinner during the processes of their formation and development; (2) their appearance rates are independent upon the geomagnetic actively Kp or the sunspot number R; (3) both of them mainly appear in winter and spring. Of course, their diurnal behaviour are difference the Ess mainly appear in the afternoon while the Em mainly appear after midnight. Therefore, It is concluded that both Ess and Em are conneced with the convergent null in the vertical drift velocity of ionization, i.e., these phenomena are caused by the same dynamic process in the vally region of the ionosphere.
The Factors Which Influence the fmin and the Possible Cause of the "Winter Anomaly" of the D Region
Shen Chang-shou
1984, 4(2): 135-141. doi: 10.11728/cjss1984.02.135
Abstract(1414) PDF 470KB(816)
Abstract:
Different statistical methods are used to analyze the various possible effects of the solar activity (2800 MC radiation intensity F (2800 MC), SID events), the geomagnetical activity (SSC events, Kp index) and meteorological factors ( Tat 50 mb altitude) on the winter anomaly in the ionospheric absorption of radio waves. The noon fmin data from the ionosonde in Beijing are taken as the index of the ionospheric absorption.The fmin = fmin -fmin (27 days running average) are found to be well related to the F = F-F (21 days running average) and also many noon fmin events (fmin> 0.2 MC) are found to follow the strong SIDevents especially in summer. The significant effects of the solar activity, which are not included in the so-called ionospheric absorption anomaly, are removed from the other analysis carefully.From our work, compared with geomagnetical factor the meteorological factor is the favourite one for explaining the anomaly.The superposed epoch method is used to show the relationship between the fmin event days (as key days) and Kp (the sun of eight numerical planetary Kp indices for each U T. day) as well as T (50mb) (temperature deviation form the 11 days running average). The T (50 mb) are found to increase after the fmin events without SID, and attained the maximum four days after the key days. That result is in a reasonable agreement with the theory concerning the virtical propagation of the planetary waves from the stratosphere.It seems that SSC and fmin events are not related closely in our analysis. The relationship between the Kp and the anomaly absorption is somehow ambigious here and need to be studied further.
Experimental Study on Melting of the Jilin Meteorite and Its Application in Geochemistry
Wang Dao-de, Fu Hui-fang
1984, 4(2): 142-148. doi: 10.11728/cjss1984.02.142
Abstract(1375) PDF 487KB(787)
Abstract:
The primitive Material which the Earth consists of is probably IABiron meteorite (core of the Earth) and H-group chondrite (mantle of the Earth). When the experimental temperature is higher than 1300℃, noticeable magmatic differentiation took place in the Jilin chondrite, and this is quite similar to the process of the formation of the core and mantle of the Earth. The metal-sulfide components within chondrite would sink to the core. During melting and recry-stallization of the Jilin chondrite the partial FeOin olivine can be reduced and Fe0 formed. These metal Fe also would move to the core.Some large parent meteorite bodies seem to have undergone such a process leading to the formation of some iron meteorites and achondrites. The Fe-Ni-S phase in the experimental products may serve as a indicator in identifying the cosmic chondrules.
The Relation Between Geomagnetic Storm (18 May 1910) and the Tail Structure of Halley's Comet (1910II)
Yan Lin-shan, Li Zhong-yuan, Gu Shun-yong
1984, 4(2): 149-155. doi: 10.11728/cjss1984.02.149
Abstract(1472) PDF 469KB(888)
Abstract:
In this paper, the geomagnetic storm on May 18, 1910 recorded by Lu-Kia-Pang Observatory near Shanghai that didn't corne from solar activity but came from the effects of plasma tail of Halley's comet (1910II) is explained. The difference between the time of Halley's comet ingress (transit) and storm-onset is interpreted. By means of the Hγ component figure of geomagnetic field, we try to analyse the structure of plasma tail of Halley's comet and also discuss the mechanism of geomagnetic storm.
The Relation Between the Sunspots Number and the Solar Radio Emission in the Frequency Range 1000 MHz ≤ f ≤ 9400 MHz
Yang Jian, Lou Guo-fang, Lu Ben-kui
1984, 4(2): 156-163. doi: 10.11728/cjss1984.02.156
Abstract(1467) PDF 506KB(846)
Abstract:
The analytical relations between the relative sunspot number and the solar radio flux density in the frequency range 1000 MHz≤f≤9400 MHz are given in this paper. These raletions are derived based on the methods of least squares, least percentage squares and compound least squares. The computed results show that the third order equation derived by the method of least percentage squares is the best regression equation. The solar quiet radio component obtained from this equation is consistent with the measurements of radio interferometer.
The Frequency Spectra and the Energy Distribution Factor of Magnetic Storm at Beijing Areas
Bai Tong-xia, Zhang Yu-min, Qi Qui-zhong, Zhan Zhi-jia, Feng Chang-hua
1984, 4(2): 164-172. doi: 10.11728/cjss1984.02.164
Abstract(1535) PDF 551KB(938)
Abstract:
In this paper, 80 magnetic storms during 1973-1977 are analyzed by means of the Fast Fourier Transform (FFT). The data were selected from the three observatories of Beijing, Qing Guang and Chang Li.It is get the general nature of the magnetic storm spectral components by the dispersion formula of FFTin some local areas. It is find the spectral features are nearly the same at the three observatories. The storm spectral amplitude decreases with increasing frequenecy and are linear in the logarithmic coordinate. This linear trend is obvious especially for the period range from 0.5 hours to 6.8 hours.It is calculated the spectral slopes b in this period range by means of the weighted least square fitting method, and the storm energy utilizing the parsval energy equation. All the spectral slopes of magnetic storm are close to each other. So the energy partitioning law for frequency of storm spectra is consistent.The above result is of value to a further study of the physical mechanism of magnetic storms, the physical nature of storm source, and the solar-terrestical relationship.
Determination of Silicon in Meteoritic Chondrules and Its Significance
Yi Wei-xi, Ouyang Zi-yuan, Hu Guo-hui, Zhong Hong-hai, Xu Han-qing
1984, 4(2): 173-176. doi: 10.11728/cjss1984.02.173
Abstract(1606) PDF 345KB(949)
Abstract:
The silicon abundances are determined in 20 chondrules from Jilin, Xin Yang, Boxian and Dontai meteorite and their whole rock samples by 14 MeV Neutron activation analysis. The silicon abundances are riched in chondrules compared to the whole chondrite. Systematic increasing in the silicon abundances of whole chondrites with E, H, L, LL is observed and also systematic increasing in the silicon abundances of non-magnetic chondrules from ordinary chondrites with H, L, LLis observed.The fact that the silicon abundances are riched in individual chondrules compared to the whole chondrites indicates indirectly that the chondrule formation is earlier than the matrix.