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1.
提出了一个新的太阳宇宙线日 -地传输的数学模型 ,它包括日冕粒子分布源和行星际传播方程 .根据对太阳宇宙线耀斑黑子群特征和耀斑相的观测 ,提出了多极性黑子湮没的两阶段日冕传输过程和传输方程 ,得到了与观测特征一致的日冕粒子分布源 .日冕传输的第一阶段 ,和太阳耀斑脉冲相的时间相当 ,加速粒子通过扩散很快均匀地分布在耀斑区 ,形成所谓快传播区 .第二阶段 ,加速粒子向快传播区以外的日冕区扩散并向行星际空间逃逸 ,形成慢传播过程 .日冕传输模型的数值结果和日冕传输的观测特征符合 .太阳宇宙线的行星际传播采用三维正交均匀各向异性方程描述 .最后把模型的数值结果与 1 997年 9月 2 4日事件的SOHO(SolarandHeliosphericObservatory)观测资料作了比较 .能较好地符合 .  相似文献   

2.
太阳宇宙线的行星际扰动   总被引:3,自引:1,他引:2       下载免费PDF全文
研究了太阳宇宙线在日冕区的横向传播特性,提出了具有扩散和逃逸过程的日冕分布粒子源,求出了含有该粒子源的行星际传输有源方程的解,并利用IMP-8,Helios-1和Helios-2观测到的同一事件不同空间位置的耀斑粒子资料对模型作了检验.并研究了同一质子事件在1AU处不同时间的粒子强度随经度的分布  相似文献   

3.
本文在简述当前在太阳坐标系中分析太阳风观测,研究太阳风三维结构的现状和问题的基础上,提出了太阳风参量太阳磁纬变化的概念,即在新的太阳磁坐标系中组织太阳风观测资料,分析太阳风参量相对于行星际电流片(而不是相对于太阳赤道)的空间分布。我们已做的1974年飞船观测资料分析和1976年行星际闪烁观测资料分析表明:存在着一个一致的合理的太阳风流速太阳磁纬变化规律。由此本文进一步提出了一个太阳风参量随太阳磁纬变化的背景太阳风模式。这模式不同于以前的各种无结构背景风模式(低速、平均、高速等)。文章最后讨论了这一背景结构的可能成因。  相似文献   

4.
本文提出一种用于研究太阳瞬变扰动在日球空间传播的新坐标系--瞬变源-日球电流片坐标系,并运用该坐标系以瞬变源耀斑为例,分析研究了由地球近空飞船观测到的277个耀斑-激波事件,发现:1.引起行星际激波和地球物理事件的大耀斑(Hα≥2,持续时间>半小时)的频数在耀斑-日球电流片坐标系中呈高斯分布,极值在电流片附近,那种在日面坐标系中随日面纬度呈双峰形的分布看不到了;2.当地球观测者和耀斑位于日球电流片同侧时,耀斑事件频次明显高于它们分处不同侧时的情形;3.激波参数(速度、磁场、密度和温度)呈现了同侧高于异侧,强激波多在同侧观测到;4.激波沿日球电流片方向的传播具有一定优势.上述结果表明,日球电流片的存在对瞬变扰动,如耀斑-激波在日球空间,特别是近太阳的传播可能具有重要影响.  相似文献   

5.
本文介绍了宇宙线空间物理学在我国的形成和主要研究内容,包括:(1)空间探测,有火箭探测、卫星探测;地面宇宙线台站观测;宇宙线的水下测量;(2)宇宙线空间物理学研究,有宇宙线的日地传输;宇宙线强度变化与CME事件;宇宙线的源物质与加速过程;宇宙线的地球物理效应.最后提到宇宙线与人体健康,特别是流行性感冒、大的太阳质子事件与地震现象、太阳宇宙线事件与天气和气候等的统计研究.  相似文献   

6.
分七个方面扼要评述我国太阳大气和行星际动力学领域的近期成果:(1)耀斑的储能和释能;(2)日冕物质抛射;(3)行星际准定态结构;(4)行星际扰动和激波传播;(5)太阳风中的阿尔文起伏;(6)太阳宇宙线的传播;(7)磁流体(MHD)计算方法设计.  相似文献   

7.
科学家发现地壳运动与宇宙空间发生的过程有某种相关。例如,业已发现地震的11年周期性,这一周期现象势必使人推断它是受按同样周期变化的太阳活动所制约的。已经找到了能够帮助实现这种相关关系的机制,其实质就在于行星际磁场和地球磁场的相互作用。太阳是行星际磁场的成因。此种磁场与太阳天体不断释放出来的等离子体有关,并且是由各个扇形体组成的。在一些扇形体内磁场的方向背着太阳,而在另一些扇形体内则朝向太阳。被固有磁场层包围着的地球,在围绕着太阳天体运行时,轮流进入这个扇形体区或另个  相似文献   

8.
1997年1月6日爆发的日冕物质抛射(CME)到达地球时引起了强烈的地球物理效应,CME在行 星际空间传播时,广州的多方向μ介子望远镜观测到银河宇宙线强度的变化. 本文采用 小波分析方法分析了磁暴前后广州台宇宙线强度的频谱变化特征,结果表明,在磁暴前 宇宙线周期为16~32h的信号发生了较明显的变化,其中周期为24~32h的周期特征过去没有 被报道过. 广州台垂直方向宇宙线强度的谱在磁暴发生前48h就出现明显的变化,比各向异 性分析方法得到的时间提前量更大. 同时还分析了几个方向宇宙线强度的最强信号以及达到 最大值的时间,并进行了简要的分析与讨论.  相似文献   

9.
本文分析了有太阳耀斑系统观测资料以来(1936年至1978年)太阳特大耀斑与磁扰的对应关系。并对不同K_p 类型所对应的行星际空间扰动结构进行了初步分析。讨论了决定磁扰形态特性的行星际传播因素。  相似文献   

10.
提出了一个太阳脉冲和经变耀斑中高能太阳宇宙线电子能谱的形成模型,探讨了高能电子通过日冕捕获区的库仑损失、轫致辐射和同步辐射等物理过程,首次研究了日冕等离子体尾场对太阳宇宙线电子的加速及其能谱的形成.所得结果和观测谱能很好地符合,从而较合理地阐明了脉冲耀斑和经变耀斑两类太阳宇宙线高能电子谱的结构.  相似文献   

11.
This work represents a physical interpretation of cosmic ray modulation in the 22nd–24th solar cycles, including an interpretation of an unusual behavior of their intensity in the last minimum of the solar activity (2008–2010). In terms of the Parker modulation model, which deals with regularly measured heliospheric characteristics, it is shown that the determining factor of the increased intensity of the galactic cosmic rays in the minimum of the 24th solar cycle is an anomalous reduction of the heliospheric magnetic field strength during this time interval under the additional influence of the solar wind velocity and the tilt angle of the heliospheric current sheet. We have used in the calculations the dependence of the diffusion tensor on the rigidity in the form K ij R 2?μ with μ = 1.2 in the sector zones of the heliospheric magnetic field and with μ = 0.8 outside the sector zones, which leads to an additional amplification of the diffusion mechanism of cosmic ray modulation. The proposed approach allows us to describe quite satisfactorily the integral intensity of protons with an energy above 0.1 GeV and the energy spectra in the minima of the 22nd–24th solar cycles at the same value of the free parameter. The determining factor of the anomalously high level of the galactic cosmic ray intensity in the minimum of the 24th solar cycle is the significant reduction of the heliospheric magnetic field strength during this time interval. The forecast of the intensity level in the minimum of the 25th solar cycle is provided.  相似文献   

12.
The propagation of cosmic rays in the Earth??s atmosphere is simulated. Calculations of the omnidirectional differential flux of neutrons for different solar activity levels are illustrated. The solar activity effect on the production rate of cosmogenic radiocarbon by the nuclear-interacting and muon components of secondary cosmic radiation in polar ice is studied. It has been obtained that the 14C production rates in ice by the cosmic ray nuclear-interacting component are lower or higher than the average value by 30% during periods of solar activity maxima or minima, respectively. Calculations of the altitudinal dependence of the radiocarbon production rate in ice by the cosmic radiation components are illustrated.  相似文献   

13.
The effect of solar and galactic cosmic ray variations on the duration of elementary synoptic processes (ESPs) in the Atlantic-European sector of the Northern Hemisphere has been studied. It has been found that solar cosmic ray (SCR) bursts result in an increase in the duration of ESPs, which belong to the western and meridional forms of atmospheric circulation. Forbush decreases in galactic cosmic rays (GCRs) are accompanied by an increase in the duration of ESPs, which belong to the meridional atmospheric circulation form, and in a decrease in the duration of ESPs, which are related to the western and eastern circulation forms. It has been assumed that the observed variations in the ESP duration are caused by the effect of short-period cosmic ray variations on the intensity of cyclonic processes at middle and high latitudes, namely, the regeneration of cyclones near the southeastern coast of Greenland after SCR bursts and the development of blocking anticyclones over the northeastern Atlantic, Europe, and Scandinavia during GCR Forbush decreases.  相似文献   

14.
The solar wind modulates the flux of galactic cosmic rays impinging on Earth inversely with solar activity. Cosmic ray ionisation is the major source of air's electrical conductivity over the oceans and well above the continents. Differential solar modulation of the cosmic ray energy spectrum modifies the cosmic ray ionisation at different latitudes, varying the total atmospheric columnar conductance. This redistributes current flow in the global atmospheric electrical circuit, including the local vertical current density and the related surface potential gradient. Surface vertical current density and potential gradient measurements made independently at Lerwick Observatory, Shetland, from 1978 to 1985 are compared with modelled changes in cosmic ray ionisation arising from solar activity changes. Both the lower troposphere atmospheric electricity quantities are significantly increased at cosmic ray maximum (solar minimum), with a proportional change greater than that of the cosmic ray change.  相似文献   

15.
The dependence of cosmic ray north-south anisotropy on the distance of the Earth to the IMF neutral current sheet has been studied. It has been indicated that the value of this anisotropy increases with increasing distance of the current sheet, and the anisotropy direction depends on polarity of the global solar magnetic field and on the sign of the IMF sector.  相似文献   

16.
We study the cosmic ray modulation during different solar cycles and polarity states of the heliosphere. We determine (a) time lag between the cosmic ray intensity and the solar variability, (b) area of the cosmic ray intensity versus solar activity modulation loops and (c) dependence of the cosmic ray intensity on the solar variability, during different solar activity cycles and polarity states of the heliosphere. We find differences during odd and even solar cycles. Differences during positive and negative polarity periods are also found. Consequences and implications of the observed differences during (i) odd and even cycles, and (ii) opposite polarity states (A<0 and A>0) are discussed in the light of the modulation models, including drift effects.  相似文献   

17.
The distinguished directions, dependent on the solar wind velocity and IMF line position, exist in the interplanetary space, which results in the nonuniform distribution of phases and the amplitude-phase interrelation of the first cosmic ray anisotropy harmonic. The characteristics of the first anisotropy harmonics, determined for each hour using the global survey method based on the worldwide neutron monitor network from 1957 to 2010, were used to study long-period variations in the cosmic ray anisotropy. The longitudinal distributions of the cosmic ray vector anisotropy and the interrelation between the anisotropy amplitude and phase have been obtained for each year in this time interval. The results evidently demonstrate the anisotropy variations caused by the solar magnetic and activity cycles. The anisotropy distributions at different solar wind velocities have also been studied. Periods with a specific cosmic ray anisotropy behavior are distinguished and discussed. The obtained cosmic ray anisotropy variations agree with the convection-diffusion anisotropy model.  相似文献   

18.
19.
The period of interplanetary, geomagnetic and solar disturbances of September 7–15, 2005, is characterized by two sharp increases of solar wind velocity to 1000 km/s and great Dst variation of the geomagnetic field (~140 nT). The time variations of theoretical and experimental geomagnetic thresholds observed during this strong geomagnetic storm, their connection with solar wind parameters and the Dst index, and the features of latitudinal behavior of geomagnetic thresholds at particular times of the storm were studied. The theoretical geomagnetic thresholds were calculated with cosmic ray particle tracing in the magnetic field of the disturbed magnetosphere described by Ts01 model. The experimental geomagnetic thresholds were specified by spectrographic global survey according to the data of cosmic ray registration by the global station network.  相似文献   

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