1989 Vol. 9, No. 1

Display Method:
TWO EVENTS SHOWING THE INTERACTION OF INTENSE MAGNETIC CLOUD WITH COROTATING HIGH SPEED STREAMS
Zhang Gong-liang
1989, 9(1): 1-12. doi: 10.11728/cjss1989.01.001
Abstract(1730) PDF 768KB(993)
Abstract:
Two intese magnetic clouds interacted with same corotating high-speed solar wind stream recurring in two successive rotations during the fall of 1978. For the August 27, 1978 event, an intense magnetic cloud was overtaken by a corotating high speed stream, the first half of the cloud can be identified with the cloud body that still retains the basic properties of a simple intense cloud; while the second half is the interaction region resulted from the overtaking magnetic cloud by the high speed stream, the speed profile of which displays a two-steps feature. For the September 25, event, another extraordinary intense magnetic cloud was overtaking the corotating high speed stream recurring again, the first half of the cloud can be identified with an interaction region; while the second half is the cloud body itself with a rather complex structure than the simple cloud without interactions. In the second case, the bulk velocity reached a very high peak value greater than 900km/s in the interaction region, also the Alvenic speed a very high value above 600 km/s in the cloud body which was very close to the local solar wind speed. These two events discussed in this paper show further the important role played by an enhancement of the Alfvenic speed in accelerating the magnetic cloud. The properties of the geomagnetic storm and the cosmic ray decrease caused by the clouds are also briefly discussed in association with the Kp category of geomagnetic storm proposed by he author.
A TWO-DIMENSIONAL MODEL OF THE WESTWARD TRAVELING SURGE
Song Li-ting
1989, 9(1): 13-19. doi: 10.11728/cjss1989.01.013
Abstract(1709) PDF 445KB(978)
Abstract:
The westward traveling surge (WTS) of aurora is defined as an important signature of the substorm onset. It is a special motion form of aurora which appears in the wake of the precipitation of the electric particles. There have been many works about calculating of electric field, conductivity and field-line current distribution in polar region during WTS. This paper puts forward a dynamic model of WTSin two-dimension plane. With the beginning of the sbsorm and following the precipitation of the electrons into inosphere, the gradient of ion density occurs (gradient of sonductivity). At the same time low frequency drift wave is excited in background electric field and its propagation reflects the main feature of WTSmotion.
SOME NOTES ON THE IONOSPHERIC CORRECTION FOR VHF INTERFEROMETER SYSTEMS IN RADIO ASTRONOMY
Han Wen-jun
1989, 9(1): 20-26. doi: 10.11728/cjss1989.01.020
Abstract(1666) PDF 507KB(607)
Abstract:
Associating the measurement methods and considering the relations between the parameters of the equipment and those of the ionosphere, various methods of ionospheric corrections are discussed in this paper. The main conclusions are: (1) The criteria to compare various methods are that the ionospheric parameters must be measured in real time and position as the observation of individual radio source; the time interval during which the ionosp heric parameters are measured must be same as that during which the data to be corrected are me asured. (2) As the radio source is strong ennough, it is reasonable to use the mean feature of the ionsphere during about 10 seconds to mabe ionospheric correction for the ionospheric model method and dual frequencymenop. but for the reference radio point source method, taking Dmax=1 km, the mean feature of the ionosphere during about 3 minuts must be used. (3) When the scale of the irregulaties of the ionosphere is larger than the base line length, the ionospheric influence can be eliminated effectively by utilizing the reference radio point source method, as the reverse condition is true, closure phase technique is more desirable. (4) If dual frequency observation is applied, the dual frequency method is the most reasonable one to eliminate the influence of the ionosphere.
THE FEATURE OF THE REFLECTANCE SPECTRA OF UNEQUIUBRIUM QINGZHEN ENSTATITE CHONDRITE (EH3)
Li Zhao-hui, Ouyang Zi-yuan, Deng Ren-da, Ding Xuan
1989, 9(1): 27-32. doi: 10.11728/cjss1989.01.027
Abstract(2800) PDF 426KB(1039)
Abstract:
The visible and near-infrared reflectance spectra. of unequilibrium Qingzhen enstatite chondrite (EH3) were measured. It is found that the reflectance spectra are different not only from those of Abee enstatite chondrite (EH4), showing Ni, Fe metal signature, but also from those of EH5 and EL6 enstatite chondrite, showing troilite feature. These unusual reflectance spectra of Qingzhen chondrite may originate from its metal grains which are coated with an accretionary layer of optical thickness. The layer is probably composed of perryite and/or mixture of perryite and sulfide. These metal grains probably have very low oxygen fugacity and are very easy to be oxidized by. air. The cosmochemical mechanism causing different reflectance spectra features of EH3, EH4, EH5 and EL6 enstatite chondrites are discussed.
The Ground-Based Double-Boom Electric Field Detector
Li Yan, Zhuang Hong-chun, Ding Jian-gang, He Yu-hun
1989, 9(1): 33-44. doi: 10.11728/cjss1989.01.033
Abstract(1677) PDF 695KB(1217)
Abstract:
The principle, structure and property of a kind of ground-based double-boom electric field detector is described here. The atmospheric electric condition represented by the typical recording is analysed. The conception of equipatition of frequency is proposed. The characteristic resistance value is calculated through the analysis of the typical detected data. According to the analysis of the joint measurements with an electric field mill, a method is proposed to distinguish the fluctuation of the local electric condition and the influence from the upper atmospheric electric condition.
CALCULATION OF EFFECTIVE CHARGES OF SOLAR ENERGETIC PARTICLES
Chen Gui-fu, Huang Yong-nian
1989, 9(1): 45-51. doi: 10.11728/cjss1989.01.045
Abstract(2017) PDF 412KB(1083)
Abstract:
This paper presents a new idea by correlating the effective charges of ions in solar energetic particles with their energies during the acceleration in flaring region. Based on ionization potentials of elements and taking account of the effect of thermal velocities of electrons in plasma of flare active region, one formula is suggested to calculate charge states of the elements C, N, O, Ne and another formula for Fe. From the formulae, the calculations for the elements are in good agreement with the observations.
DIFFERENTIAL DOPPLER TRACKING FOR THE EQUATORIAL ANOMALY CRESTS OF THE IONOSPHERE
Liu Xuan-mou, Huang Tian-xi, Liu Rong-dao
1989, 9(1): 52-57. doi: 10.11728/cjss1989.01.052
Abstract(1775) PDF 417KB(950)
Abstract:
In this paper, the differential Doppler measurements for the equatorial anomaly crests in Wuhan (30.5°N, 114.4°E) is presented. The study of the experimental data indicates that the equatorial anomaly crests in the Far East is situated somewhere between Changsa (28.1°N, 113.0°E) and Guangzhou (23.2°N, 113.3°E). The northern hump of the equatorial anomaly is mostly between Hengyang (26.8°N, 112.5°E) and Yingde (24.2°N, 113°E). Some useful results about hump behaviour are also given.
SOME CHARACTERISTICS OF IONOSPHERIC ELECTRON CONTENT MEASURED AT BEIJING STATION
Jiang He-rong, Xu Chu-fu
1989, 9(1): 58-63. doi: 10.11728/cjss1989.01.058
Abstract(1754) PDF 379KB(852)
Abstract:
The ionospheric electron content (IEC) has been measured at Beijing for almost a whole solar cycle since 1980. From the analysis of the data, the following conclusions are obtained: there are undisturbed diurnal double-peak variations, noctural peak and a specific two-peak curves showing a subpeak before noon and a main peak after noon, although the variations of diurnal, seasonal and annual IECare recorded in high probability. It is the purpose of this paper to give the double-peak characteristics and nocturnal peak at Beijing and their variation in solar cycle. The results is compared with those of other scientists.
There is Seasonal Abnormal Phenomenon in Night Time f0F2
Suo Yu-chang, Li Yong-sheng, Wei Min-jun
1989, 9(1): 64-69. doi: 10.11728/cjss1989.01.064
Abstract(1858) PDF 398KB(1176)
Abstract:
Using data of nine ionospheric stations of China during Dec., 1975-Dec., 1986, it is presented that under the conditions of certain latitudes and solar activity, night time f0F2 shows a seasonal anomaly similar to that of the daytime foFz. This anomaly obviously shows two features: it only occurs in low latitudes; the higher solar activity is, the larger exlent of the degree of the anomaly is to. The night time seasonal abnormal phenomenon is the continuation of daytime seasonal abnormal phenomenon. The promary mechanism of the phenomenon is the seasonal variation of neutral air (O, O2, N2) concentration ratio O/O2 and O/N2, caused by the summer hemispher to winter hemisphere air flow. It is analysed why the night time seasonal abnormal phenomenon is limited in low latitudes and why the abnormal degree changes with solar activity.
ON DETERMINATION OF THE TOTAL ELECTRON CONTENT FROM OBSERVATION DATA OF DIFFERENTIAL DOPPLER MEASUREMENT
Han Gui-lin
1989, 9(1): 70-73. doi: 10.11728/cjss1989.01.070
Abstract(1604) PDF 275KB(988)
Abstract:
This paper discusses a computing method for differential Doppler observation data to obtain informations of ionospheric total electron content.
THE VARIATION OF THE ATMOSPHERIC CYCLONE DURING GEOMAGNETIC STORMS
Ye Zong-hai, Xue Shun-sheng
1989, 9(1): 74-78. doi: 10.11728/cjss1989.01.074
Abstract(1743) PDF 349KB(944)
Abstract:
This paper provides a statistical study of the variation of the Atmospheric Vorticity Area Index (VAI) during geomagnetic storms for 1966-1978. The results show that the influence of geomagnetic storms on VAIis very obvious. VAIincreases evidently when geomagnetic storms occur, then VAIdecreases, and the maximum decrease occurs on the fourth day after geomagnetic storms. But the variation characteristic of VAIduring each type of geomagnetic stoms is different, and there is obvious season effect in the variation of VAI.