空间科学学报

1983 Vol. 3, No. 4

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THE FILAMENTARY STRUCTURE IN SUNSPOTS

Hu You-qiu

1983, 3(4): 261-268. doi: 10.11728/cjss1983.04.261

Abstract(2289) PDF 569KB(871)

Abstract:
The present paper is intended to discuss the non-axisymmetric filamentary structure in sunspots.Given the geometric shape of the field lines,analytic solutions are presented for both zeroth-and first-order equations of magnetostatic equilibrium.It shows that in those regions with stronger magnetic fields both gas pressure and temperature become lower.As far as the density is concerned,it may get higher or lower,depending upon the actual non-axisymmetric structure of magnetic field in sunspots.In the former case,the increase of density and the decrease of temperature will both bring about a decrease of brightness.In the later case,the changes of density and temperature have opposite effects on the brightness.Under the present model,however,it turns out that the decrease of temperature always predominates over that of density.We conclude,therefore,that dark penumbral filaments are associated with strong magnetic fields.

THE GOVERNING EQUATIONS OF THE VARIATION OF ALFVENIC FLUCTUATIONS

Tu Chuan-yi

1983, 3(4): 269-279. doi: 10.11728/cjss1983.04.269

Abstract(2269) PDF 930KB(964)

Abstract:
A group of equations governing the incompresible small time scale fluctuations in interplanetary magnetic field are derived from the MHD equations.The discusion of the governing equations show that the radial variation of the amplitude of the fluctuation can be discribed by the Alfven wave WKB model only at the small amplitude limite.When the amplitude of the fluctuation is finite with respect to the average magnetic field intensity,the nonlinear terms in the garvening equations can not be droped and the WKB aproxima-tion fails.That is the reason why the radial variation of the amplitude of the Alfvenic fluctuations from 0.3 AUto 1 AU observed by Heios does not agree with the WKBwaves model.According to the properties of the governing equations,a qualytative model for the propegation of Alfvenic fluctuations is presented.Alfvenic fluctuations can be considered to be in zeroth-order conpoused of many waves with different wave numbers propogating from the Sun towards away,but some wave modes in first-order will be generated,the nonlinear interactions between the zeroth order waves and the first order waves cause an energy cascading to high frequency range.The amplitude of the zeroth-order wave will be modified not only by the large scale variation of the solar wind but also by the cascading process.This model can explain some properties of Alfvenic fluctuations qualitatively.

THE FLARE ON THE SOLAR DISK ON JULY 14,1980 AND EMF FLARE MODEL

Tang Yu-hua, Xu Ao-ao

1983, 3(4): 280-286. doi: 10.11728/cjss1983.04.280

Abstract(1973) PDF 543KB(664)

Abstract:
In this paper,a comprehensive study of flare of 14,July 1980 is presented by using the patrol,of H_α,white light,S₂HG observational data obtained at Yunnan observatory,radio data at Beijing observatory and X-ray data from SMM.Compared with EMF (Emerging Magnetive Flux) model,the morphology features of the active region are analysed and the magnetic energy which is released during the flare,the characteristic time of the flare process,the total number of accelerating electrons during the flare eruption and average energy of accelerating electrons are estimated.The results show that:1,EMF model is in good agreement with the observations.2,On the basis of the velocity data and analysis for the site of flare eruption.It seems that the node and nearby region of velocity neutral line and magnetic neutral line (or dark filament) is probably the position of the current sheet.3,The observational results show that the hard X-ray burst is produced by high energy non-thermal electrons accelerated in the current sheet.But solf X-ray burst is produced by hot bremsstrahlung of high-temperature plasma in the flare region.

THE THEORETICAL CALCULATION OF THE ELECTRON ENERGY SPECTRUM OF AN INVERTED-V EVENT

Liu Zhen-xing, Huang Ying-lei

1983, 3(4): 287-294. doi: 10.11728/cjss1983.04.287

Abstract(2085) PDF 667KB(1081)

Abstract:
Observations show that there is a acceleration region on the high-latitude auroral field lines at the altitudes ranging from 2000 km-8000 km.It is pointed out in this paper that plasma sheet electrons are accelerated by the electrostatic waves turbulence and the large scale DCparallel electric field within-the acceleration region to form inverted-Vstructures.The equation of the electron energy spectrum is derived using the quasi-linear kinetic equation,and the solution of the energy spectrum is obtained.The main characters of the electron energy spectrum can be explained by this theory.

PARAMETRIC EXCITATION OF ELECTROSTATIC ION CYCLOTRON WAVES IN THE AURORAL ZONE

Wang Yuan-dian, Li Fang

1983, 3(4): 295-299. doi: 10.11728/cjss1983.04.295

Abstract(1962) PDF 471KB(1001)

Abstract:
Parametric process in which lower hybrid wave decays into electrostatic ion cyclotron wave and whistler wave in the auroral zone is analysed.The results show that,with the wave amplitude of the pump from 40 mV/m to 100 mV/m,the growth rate of the excited electrostatic ion cyclotron wave can reach 0.2-0.5 ω_ci,which is larger than the expected values by such linear mechanisms as current-driven instability and ion-beam instability.Therefore,when the amplitude of the pump is larger than 40 mV/m,the parametric excitation of electrostatic ion cyclotron wave may be the dominant mechanism.

THE INFLUENCES OF THE IMF SECTOR BOUNDARIES OF FOUR DIFFERENT TYPES ON THE GEOMAGNETIC FIELD ACTIVITY

Zhang Shu-li

1983, 3(4): 300-304. doi: 10.11728/cjss1983.04.300

Abstract(2222) PDF 387KB(954)

Abstract:
The influences of the IMF sector boundaries of four types on the geomagnetic field activity have been studied statistically.It is found that when a sector boundary with magnetic field intensity increasing and magnetic field direction orienting southward sweeps the earth,the value of the D_st index begins to increase and achieve its maximum value in about 11 hours,which is the shortest time for the D_st to achieve its maximum in the four types of the sector boundaries which have been studied in this work.

ON THE DEVELOPMENT OF IONOSPHERIC E_s-s OVER WUCHANG,CHINA AND ITS RELATED FACTORS

Tan Zi-xun, Huang Xin-yu, Wang Shen

1983, 3(4): 305-309. doi: 10.11728/cjss1983.04.305

Abstract(1911) PDF 448KB(952)

Abstract:
In this paper,data of ionospheric E_s-s over Wuchang,China are analyzed and theoretical investigation are made.It shows that:(1) The occurrence of E_s-s is in proportion to a factor K=1/G(f⁰Ef_min (2)The occurrence of E_s-s is also clearly influenced by the power of the equipment used.(3)E_s-s seems to be a phenomenon in non-magnetically disturbed days,which is due to the fact that the observability is limited by the high f_min in disturbed days.(4)Proper related phenomena exist both as "the prelude" and "the postlude" to the occurrence of E_s-s over Wuchang.Generally,there also exists stratification due to acoustic gravity waves.Judging from these and other ionospheric features over Wuchang,the lunar effect may serve as a common source.

ERROR ANALYSIS OF DYNAMICALLY TUNED GYROSCOPE RESULTING FROM TWIN SPIN FREQUENCY ANGULAR VIBRATION

Wang Hui-nan

1983, 3(4): 310-322. doi: 10.11728/cjss1983.04.310

Abstract(2324) PDF 998KB(730)

Abstract:
With a simplified analytical method,this paper presents both the dynamically tuned condition of a multigimbal dynamically tuned gyroscope and the condition of eliminating error torques resulting from a given twice spin frequency angular vibration inputs of the driving shaft.The obtained results include the corresponding results of the single or two-gimbals gyro which can be seen in the references.If the plane of inner and outer torsion springs is not orthogonal to the driving shaft,this paper presents the dynamically tuned condition,and in this case,this paper examines how tuned gyro's drift is affected by the error torque resulting from a given twice spin frequency angular vibration of the driving shaft.

EFFICIENCY ENHANCEMENT OF MULTI-HEADED Ge SYSTEM FOR SPACE γ-RAY SPECTROSCOPY

Ma Yu-qian

1983, 3(4): 323-332. doi: 10.11728/cjss1983.04.323

Abstract(1973) PDF 809KB(925)

Abstract:
In γ-ray line observations the multi-headed Ge crystal system is used for improving spectrometer's sensitivity.In this paper Monte-Carlo simulations have been made to investigate the performance for a 9-headed Ge cluster.The loss energy spectra distributions in the crystals,detective efficiencies,full energy efficiencies and their increases under some different combinations of crystals' outputs have been presented.Measurements in the laboratory with an actual detector shows good agreements with simulations.

THE ANALYSIS OF GEOMAGNETIC AND SOLAR ACTIVITIES DURING SMY AND TWENTY FIRST SOLAR CYCLE

Gao Mei-qing, Shi Zhong-xian, Zhang Gong-liang, Jing Wen

1983, 3(4): 333-341. doi: 10.11728/cjss1983.04.333

Abstract(2357) PDF 858KB(900)

Abstract:
This paper compares sunspots,Geomagnetic Ap indexes,numbers of ≥2 solar flares,magnetic storms and first,second and third large magnetic storms every solar cycle during 17th-21st solar cycle.The result is in agreement with the prediction of the first writer for geomagnetic maximum of 21st solar cycle.The geomagnetic activity during the 21st solar cycle is higher.This paper analysis of the numbers of ≥2 solar flares and distributionof magnetic storms has been made.Percentage of magnetic storms resulted by 3 solar flares is lower than 19,20 cycle.Type IVand metre wave radio burst are considered to be important conditions to produce magnetic storms.Some typical example of the largest magnetic storms,the largest radio burst resulting magnetic storms,the most severe short wave communication disturbance in ionosphere and magnetic storms resulted by the large solar flare with bright mass ejection and two-ribbon flares are also given.In the end an analysis has been made on the 22 spotless flares during SMY (Solar Maximum Year).There spotless flares may result medium and small magnetic storms.

英汉空间物理词汇(续)

1983, 3(4): 342-353. doi: 10.11728/cjss1983.04.342

Abstract(2559) PDF 1352KB(777)

Abstract: