1988 Vol. 8, No. 1

Display Method:
The Fine Structure and Evolution of a Subflare
Shi Zhong-xian, Chen Jian, Wang Jing-xiu
1988, 8(1): 1-11. doi: 10.11728/cjss1988.01.001
Abstract:
A complete set of data of a-N importance Ha flare,the firbril structure (0.6") of which is very clearly started at 1613 UT on May 8,1981 was obtained at Big Bear Solar Observatory.The image processing is made for Ha filtergrams,and the isophotes are drawn then.The fine structure and evolution are obtained with two methods.One is to measure luminosity variation for 50 fixed bright points relative to well-chosen stable brightness feature,which is called fixed point method.The other is to follow the brightest point and to measure its position changes time by time,which is called bright point tracing.The following results are revealed:A.In the bright patches of this flare,the first brightening points and brightest points at the maximum enhancement of radiation are not at same position.The brightening points show systematic displacement.B.Each flare patch,at least,has two kernels with typical size of 2" 3".5.The luminosity of all pixels (0.6") in the some kernel changes in phase.Different kernels have different luminosity variation patternsC.The light curves of Ha flare and the microwave burst look similar.Ha luminosity gradually enhances during microwave preburst;the flash phase of Ha begins after the main burst of microwave;the Ha luminosity reaches its maximum after the main burst of microwave for several seconds.D.Patch C and patch B are separated for about 50 Mm and they brighten at different time.The brighterning of C is delayed for ten seconds comparing with that of the B.Assume constant a force-free magnetic configuration above active regions,the chromosphere magnetic fields by using Chiu and Hilton method (1977) are extropolated.It is found that patch C and patch B do connect each other by magnetic field lines when the factor is chosen to be 0.418.Further assume the generation and propagation of Alfven waves are from flare source,it is-found that the Alfven traillvng time from flare source to B is 0.3 seconds,while to C is 9.3 seconds,which seems to be the responsible delay time of the brightening of C comparing to B.Same calculation was made for patch A and patch C.However the delay time of the brightening of C comparing with A is not compatible with Alfven travelling time.It might mean that the A and C is not connected with magnetic field lines.
Semiempirical Models of the Impulsive Phase of the Chromospheric Flare
Gan Wei-qun, Fang Cheng
1988, 8(1): 12-19. doi: 10.11728/cjss1988.01.012
Abstract(1489) PDF 588KB(690)
Abstract:
In this paper,the detailed semiempirical models representing the chromospheric state during the impulsive phase of the 2B flare on Feb.3,1983 are proposed.The physical pictures of total evolutionary pattern of the impulsive phase of the flare are improved either quantitatively or qualitatively in comparison with the former work we did.Based on these semiempirical models,some dynamical properties and energy processes are also discussed.
A Study on the Non-uniformity of HIPPARCIS' Scanning Observations
Ling Zhao-fen
1988, 8(1): 20-25. doi: 10.11728/cjss1988.01.020
Abstract(1542) PDF 450KB(887)
Abstract:
The simulated number of observations for the fifty stars distributed on the whole sky are calculated with four different revolving angles (30°,36°,43° and 50° and the observing period of half year.It is found that the number of observations goes up with increasing β.It reaches the maximum as the observed star located between 40° and 60°in the ecliptic latitude.But the number of observations for the stars between 0°and 10° is about half of the maximum.The results is consistent with the previous theoretical estimates by Hoyer's group.It is pointed out by this paper that the enhanced accuracy near 60° latitude is due mainly to more scanning observations.
Transport of the Interplanetary Fluctuations to the Magnetopause
Du Heng, Wei Feng-si, Y. C. Whang
1988, 8(1): 26-34. doi: 10.11728/cjss1988.01.026
Abstract(1430) PDF 741KB(1307)
Abstract:
Fluctuations in solar wind velocity and magnetic field or relatively large amplitude on a time scale of the order of minutes are presented in interplanetary space essentially all the time.These fluctuations are transported to the region immediately outside the boundary surface of the magnetosphere.They may play an important role in the interaction of the magnetosheath plasma with the magnetopause.The interplanetary fluctuations first make a jump across the earth's bow shock.After the jump,some fluctuations are carried to reach the boundary surface of the magnetosphere.The amplitude of fluctuations at the surface of the magnetosphere is considerably amplified as compared with the interplanetary fluctuations.The solar wind conditions upstream of the bow shock control over the amplification factor This simulation study suggests that large Alfvenic fluctuations are presented at the boundary surface of the magnetosphere if the upstream fluctuations are large.The amplification factor becomes very large when the upstream magnetic field is nearly perpendicular to the sun-earth line and the amplification factor also increases with incressing plasma beta value and/or increasing Alfvenic Mach number.The effect of the state of upstream anisotropy on the amplification factor is relatively small.The present of large fluctuations indicates that no steady laminar flow exists in the boundary layer of the magnetosphere.
Two Possible Modes of the Interactions Between the Solar Wind and the Magnetosphere
Liu Shao-Iiang, Chen Jian-li
1988, 8(1): 35-38. doi: 10.11728/cjss1988.01.035
Abstract(1571) PDF 353KB(691)
Abstract:
The correlation analyses between the solar wind parameters (V,T,N and Bz) and the geomagnetic activity for the different periods of solar activity of 20th solar cycle are carried out.Further more,the solar wind parameters and its daily RMS of hourly mean values are compared to geomagnetic activity via regression analyses for the solar maximum and minimum years of the same cycle.The results show that in addition to the magnetic storms due to the reconnection between the IMF and the earth's magnetic field,which is accepted generally,there is another geomagnetic disturbance which is independent of Bz and is caused by solar wind with high temperature,high speed and thermo-nonumiform.
Kelvin-Helmholtz Instablity on the Magnetopause (IV) Some Properties of Compressible Surface Wave
Pu Zu-yin, M. G. Kivelson
1988, 8(1): 39-46. doi: 10.11728/cjss1988.01.039
Abstract(1635) PDF 575KB(593)
Abstract:
In this paper,several properties of the compressible Kelvin-Helmholtz unstable waves on the magnetopause including the phase relationship between δB and dp,the polarization of δB,the spatial growth rate and it's local time effects on the geomagnetic pulsations and the response of K-H unstable waves to the variations of IMF are investigated.It is shown that knowing these properties is very helpful in understanding the generations of both MHD weves in the magnetospheric boundary region and low frequency geomagnetic pulsstions.
The Gamma-ray Energy Output from Supernova Explosion
Dai Kai-mei, Qian You-neng
1988, 8(1): 47-52. doi: 10.11728/cjss1988.01.047
Abstract(1452) PDF 468KB(753)
Abstract:
Using a two box model,the dependence of 14C concentration in the atmosphere on the 14C production rate,the inventories and residence time of carbon in the atmosphere and ocean are deduced.Then a formula for calculating the increment of 14C nucleon number in atmosphere after a supernova explosion according to tree ring 14C data and a formula for estimating the gamma ray energy output emitted from the explosion are successively given.
The Burgers-KdV Equation of Ion Acoustic Waves
Song Li-ting
1988, 8(1): 53-59. doi: 10.11728/cjss1988.01.053
Abstract(1484) PDF 482KB(1086)
Abstract:
It is extensively used in the applied science that nonlinear system is reduced to a tractable single nonlinear equation by reductive perturbation method (RPM).RPM is efficient for dissipative system or dispersive system.But when the nonlinear system contains both dissipative and dispersive effects this method is not applicable.In this paper some changes are made to this method for the ion acoustic wave in plasma.And as a result,the Burgers-KdV equation is derived.This paper also discusses its solution.
An Analysis of Several Effects on the Maintenance of Night-E Region
Chen Pei-ren
1988, 8(1): 60-65. doi: 10.11728/cjss1988.01.060
Abstract(1550) PDF 498KB(942)
Abstract:
Several effects on the maintenance of night-E region,such as geocoronal scatter,particle preciapitation,neutral winds and the joule heating of the electrojet current,are discussed.The function of each effect in different time,different latitude is also analysed.
Study of Motion of Spinning Satellite with Spherical Tank on Center Partially Filled with Liquid
Wang Zhao-lin, Liao Min Deng, Zhong-ping
1988, 8(1): 66-74. doi: 10.11728/cjss1988.01.066
Abstract(1469) PDF 610KB(769)
Abstract:
The problem of liquid sloshing in a partially filled spinning spherical tank is analyzed in this paper.The governing equations are basic equations of fluid and Euler equations of system.By using of a series of eigenfunctions the velocity field of fluid are calculated,based on which energy dissipation in fluid and time constant of nutation angle are estimated.
A Multi-Ribbon Structure in the Plot of Temperature and Velocity Observed by IMP 8
Tu Chuan-yi, Xu Yu-yao
1988, 8(1): 75-77. doi: 10.11728/cjss1988.01.075
Abstract(1398) PDF 710KB(718)
Abstract:
A multi-ribbon structure is found in the plot of temperature and velocity observed by IMP 8.The data is taken from the NSSDC hourly-averaged interplanetary medium compilation tape.