共查询到19条相似文献，搜索用时 171 毫秒
1.
文中选了５ 个典型活动区, 分析了这些活动区的磁场, 与活动区相应的ＣＭＥｓ, 太阳爆发事件和太阳质子事件我们发现, 对于Ｅ ≥１０ｍｅＶ 的太阳质子事件有相应的源活动区, 源耀斑和ＣＭＥ; 活动区矢量磁场有剪切, 磁场剪切越强质子事件越强; 多数在质子耀斑发生前出现磁流浮现; 太阳１０ｃｍ 射电爆发持续时间长文中结果还佐证了Ｓｈｅａｌｙ 等的结果： Ｘ 射线耀斑的长持续时间与ＣＭＥ 的发生正相关另外,在５ 个活动区中, 有三个大耀斑发生前没有明显的磁剪切作为它们的先兆, 它们是非质子源耀斑这是Ｍｏｏｒｅ, Ｈａｇｙａｒｄ 和Ｄａｖｉｓ 的磁场强剪切是耀斑产生的必要条件的反例 相似文献
2.
本文分析了１９８０ 、１９８４ 和１９８９ 年ＳＭＭ 卫星观测到的１４０ 次日冕物质抛射（ＣＭＥ） 事件在时空分布上与“冕洞边缘结构”、耀斑爆发和爆发日珥等事件的相关关系结果表明, ＣＭＥ 事件与日冕边缘结构的关系最密切此外, ＣＭＥ与赤道冕洞具有同步的长期演化关系由此认为, 冕洞边缘结构对ＣＭＥ的可能贡献是不可忽视的 相似文献
3.
在本文里, 我们对ＣＭＥ 和太阳耀斑现象的各种相互关系进行了讨论希望本文的内容能够引起天文、空间物理和地球物理等人员的兴趣, 促进ＣＭＥ的综合研究 相似文献
4.
日冕物质抛射（ＣＭＥ） 是一个极为复杂的动力学过程本文基于开放场、闭合场的物理条件及射电爆发理论, 研究了ＣＭＥｓ 与相伴随的射电Ⅱ型、Ⅲ型、Ⅳ型爆发、软χ射线增强及太阳耀斑的关系给出了它们相伴随的条件： 当磁通量喷发, 能量释放时, 等离子体将被加速如果加速区在开放场, 可能会产生Ⅲ型爆发; 如果是闭合场, 被加速的高能质子和高能电子将被磁环捕获高能质子在磁环腿部呈损失锥分布, 当Ｅ≥ＥＴ 时会产生软χ射线增强随着磁环内的热压Ｐ和磁压Ｐｍ 的升高, 当β≥βＴ 时, 磁环将炸裂, 产生ＣＭＥｓ抛射出的高能相对论电子绕开放场线作螺旋飞行时, 会产生Ⅳ型爆发; 而亚相对论电子以零入射角沿开放磁场线逃逸时, 会产生Ⅲ型爆发高速飞行的等离子体产生激波时, 会产生Ⅱ型爆发当ＣＭＥｓ 源接近耀斑时, 会触发耀斑爆发 相似文献
5.
日冕物质抛射与太阳粒子事件 总被引：1，自引：0，他引：1
本文介绍了２０多年来对日冕物质抛射与太阳粒子事件的关系和太阳粒子事件的源等方面的研究成果和进展。大量的研究表明，太阳粒子事件源于日冕物质抛射并被日冕和行星际激波加速和控制。在无耀斑源的日冕和行星际激波加速和控制。只有极少数产生太阳粒子事件，并且这些事件中多数为低能粒子事件。这些相关日冕物质抛射的共同特征是：无相关的强Ｘ射线爆发，产生的行星际激波速度较快，无激波加速，无Ⅱ和Ⅳ米波爆发。几乎所有的产生 相似文献
6.
利用１９８９ 年到１９９１ 年的观测资料, 按面积把太阳黑子群分成五类统计分析了各类黑子群的强耀斑活动（Ｉ＞ ＝ Ｍ） 结果是： Ｓｍ ＞ ＝ ５００ 的黑子群占全部黑子群的６３ ％ , 产生了５６ ％ 的强耀斑近半数的强耀斑产生于面积小于５００ 的小黑子群文中分析了小黑子群产生强耀斑的磁场位形先兆, 这些先兆有： １） 磁流浮现, （２） 磁轴垂直, （３） 反极性活动区, （４） 活动区旋转, （５）同极性磁流合并或撕裂, 但仍有相当多的小黑子群产生耀斑前无任何先兆; 用极大熵谱的ＡＲ 模式计算了四个超级活动区的强耀斑活动周期： 分析讨论了持续性预报的适用范围以及它的弊病文中指出, 发展带有更多物理意义的预报技术和方法是提高预报水平和满足用户要求的唯一可取之路 相似文献
7.
太阳质子事件期间内辐射带质子通量的变化 总被引：1，自引：0，他引：1
本文介绍风云一号（B）卫星上的宇宙线成份监测器,在1991年1月30日及31目的耀斑期间及其前后几天,对能量在4-23MeV内的内辐射带质子通量的观测结果,并对这些结果做了详细的分析.结果表明,在这两次耀斑及其所产生的太阳质子事件期间,内辐射带质子通量有显著的变化:在磁漂移壳参量L≥1.64的空间,质子通量显著增强,增幅在40％-200％之间;在L=1.30-1.60的空间,质子通量的增强也较为明显,增幅在20％以上;总的变化趋势是,L越大的地方,质子通量的增强就越显著.质子事件之后,内辐射带质子通量又逐渐回复到质子事件之前平衡结构时的水平. 相似文献
8.
2001年4月2日, 太阳爆发了一个近年来X射线通量最大的一次耀斑并伴有质子事件, 利用“资源一号”卫星星内粒子探测器和神舟二号飞船X射线探测器的观测资料, 对这一事件的高能粒子响应进行了特例研究. “资源一号”卫星运行于太阳同步轨道, 高度约800km, 和宁静时期的统计结果对比, 这次耀斑后, 星内粒子探测器在地球极盖区（地球开磁场区）观测到耀斑粒子的出现, 这是宁静时期没有的; 神舟二号飞船轨道高度400km, 倾角为42°, X射线探测器在42°中高纬地区也观测到高能电子通量比宁静时明显的增加, 这表明, 太阳耀斑引起的近地空间辐射环境的变化遍及纬度约40°以上的区域, 甚至在40°N附近400 km左右的高度上仍然有响应. 但是, 中高纬度、极光带和极盖区的粒子来源, 加速机制和响应方式却不一定相同, 需要分别讨论. 资料分析和对比还表明, 质子事件的强度并不一定和耀斑的X射线通量成正比, 因此, 近地空间高能粒子对耀斑的响应也不是完全决定于X射线强度. 相似文献
9.
利用几种不同空间位置空间天气观测数据对2006年12月系列太阳耀斑近地空间天气效应进行多方位分析,结果表明,该系列耀斑都伴随不同程度日冕物质抛射CME和高速太阳风,首轮耀斑产生超过600 km/s高速太阳风,12月6日通过L1点并持续到12月12日,12月14日次轮耀斑产生900 km/s太阳风高速流,该股高速太阳风引发12月15日地磁场特大磁暴。ACE数据显示,12月6、14、15日IMF南向分量长时间超过5 nT,14～15日有4 h以上超过10 nT,NOAA SEC发布的全球地磁综合KP指数15日超过8。磁暴期间华南地区30 min平均TEC最大值波动幅度达到10TECU或20%,表明发生了较大电离层暴。 相似文献
10.
11.
Statistical analysis is performed for the relationship of coronal mass ejections (CMEs) and X-ray flares with the fluxes of solar protons with energies >10 and >100 MeV observed near the Earth. The basis for this analysis was the events that took place in 1976–2015, for which there are reliable observations of X-ray flares on GOES satellites and CME observations with SOHO/LASCO coronagraphs. A fairly good correlation has been revealed between the magnitude of proton enhancements and the power and duration of flares, as well as the initial CME speed. The statistics do not give a clear advantage either to CMEs or the flares concerning their relation with proton events, but the characteristics of the flares and ejections complement each other well and are reasonable to use together in the forecast models. Numerical dependences are obtained that allow estimation of the proton fluxes to the Earth expected from solar observations; possibilities for improving the model are discussed. 相似文献
12.
M. I. Divlekeev 《Geomagnetism and Aeronomy》2012,52(8):1044-1049
The observations of active region (AR) NOAA 10792 in the Ca II 8498 ? line with an ATB-1 solar telescope at the Sternberg State Astronomical Institute, Moscow State University (SSAI MSU) on July 30, 2005, are illustrated, and the events are analyzed using the data obtained on spacecraft. Three flares and accompanying coronal mass ejections (CMEs) are considered. It has been indicated that the beginning of the first compact CME lagged behind the flare onset by 3 min. Plasma ascended with acceleration that reached 0.4 km/s2 at the flare maximum. The matter was also apparently accelerated after the flare maximum, since an ejection could only appear at the edge of the occulting C 2 LASCO coronograph disk at 0557 UT when acceleration is about 0.5 km/s2. The second CME (of the halo type) leaded the beginning of the corresponding flare. 相似文献
13.
V. G. Fainshtein Ya. I. Egorov G. V. Rudenko S. A. Anfinogentov 《Geomagnetism and Aeronomy》2016,56(8):1060-1067
Field variations in the region of eruptive event of June 7, 2011, associated with the filament eruption (FE), flare, and coronal mass ejection are studied based on vector measurements of the photospheric magnetic field with the SDO/HMI instrument. Variations of the module (B), the radial (Br) and transverse (Bt) components of the magnetic induction, and the inclination angle (α) of field lines to the radial direction from the center of the Sun are analyzed. It is shown that the strongest changes of the field before the event were located near the base of the southeastern leg of the eruptive filament; after the beginning of the event, they were located in the CME flare region. It is suggested that the FE is associated with two episodes of strong and rapid field variations: before the beginning of the slow filament rise and before its sudden acceleration. For the first time, variations of the inclination angles of the field lines over time in different parts of the eruptive event are studied in detail. It was found that the inclination angles of the field lines decrease in the vicinity of its channel during the slow rise of the filament, and the inclination angles of the field lines increase sharply after the beginning of the flare in the flare region in the vicinity of the neutral line. 相似文献
14.
15.
G. N. Kichigin L. I. Miroshnichenko V. I. Sidorov S. A. Yazev 《Geomagnetism and Aeronomy》2016,56(4):393-400
The analysis of observations of large solar flares made it possible to propose a hypothesis on existence of a skin-layer in magnetic flux ropes of coronal mass ejections. On the assumption that the Bohm coefficient determines the diffusion of magnetic field, an estimate of the skin-layer thickness of ~106 cm is obtained. According to the hypothesis, the electric field of ~0.01–0.1 V/cm, having the nonzero component along the magnetic field of flux rope, arises for ~5 min in the surface layer of the eruptive flux rope during its ejection into the upper corona. The particle acceleration by the electric field to the energies of ~100 MeV/nucleon in the skin-layer of the flux rope leads to their precipitation along field lines to footpoints of the flux rope. The skin-layer presence induces helical or oval chromospheric emission at the ends of flare ribbons. The emission may be accompanied by hard X-ray radiation and by the production of gamma-ray line at the energy of 2.223 MeV (neutron capture line in the photosphere). The magnetic reconnection in the corona leads to a shift of the skin-layer of flux rope across the magnetic field. The area of precipitation of accelerated particles at the flux-rope footpoints expands in this case from the inside outward. This effect is traced in the chromosphere and in the transient region as the expanding helical emission structures. If the emission extends to the spot, a certain fraction of accelerated particles may be reflected from the magnetic barrier (in the magnetic field of the spot). In the case of exit into the interplanetary space, these particles may be recorded in the Earth’s orbit as solar proton events. 相似文献
16.
《Journal of Atmospheric and Solar》1999,61(1-2):101-108
This review presents some of the new developments in the understanding of coronal magnetic fields in flares and coronal mass ejections. The modelling of the coronal magnetic field based on observed photospheric field permits to understand the location of energy release. Various flare observations are consistent with a model where magnetic reconnection occurs between two magnetic fields of different connectivity. Because magnetic helicity is almost conserved, the stored energy cannot be fully released in confined flares. The corona gets rid of the helicity injected by the convection zone only by ejecting part of the magnetic field. A severe physical constraint (open-field limit) on these ejections has been firmly established for force-free fields. It is, however, possible to open partially the field or to eject a twisted flux-tube keeping the energy of the field behind the open-field limit. New results show that in simply connected fields this happen after a finite time without loss of equilibrium, while in more complex topology a loss of equilibrium can still be present. 相似文献
17.
The results of a three-dimensional MHD simulation and data obtained using specialized spacecraft made it possible to construct
an electrodynamic model of solar flares. A flare results from explosive magnetic reconnection in a current sheet above an
active region, and electrons accelerated in field-aligned currents cause hard X rays on the solar surface. In this review,
we considered works where the boundary and initial conditions on the photosphere were specified directly from the magnetic
maps, obtained by SOHO MDI in the preflare state, in order to simulate the formation of a current sheet. A numerical solution
of the complete set of MHD equations, performed using the new-generation PERESVET program, demonstrated the formation of several
current sheets before a series of flares. A comparison of the observed relativistic proton spectra and the simulated proton
acceleration along a magnetic field singular line made it possible to estimate the magnetic reconnection rate during a flare
(∼107 cm s−1). Great flares (of the X class) originate after an increase in the active region magnetic flux up to 1022 Mx. 相似文献
18.
The sun was very active in the declining phase of solar cycle 23. Large sunspot active regions gave origin to multiple flare and coronal mass ejection (CME) activity in the interval 2003–2005. On November 2004, the active region AR 10696 was the origin of dozens of flares and many CMEs. Some events of this solar activity region resulted in two large geomagnetic storms, or superstorms (Dst??250 nT) on November 8, peak Dst=?373 nT, and on November 10, peak Dst=?289 nT. It is the purpose of this article to identify the interplanetary origins of these two superstorms. The southward-directed interplanetary magnetic fields (IMF Bs) that caused the two superstorms were related to a magnetic cloud (MC) field for the first superstorm, and a combination of sheath and MC fields for the second superstorm. However, this simple, classic picture is complicated by the presence of multiple shocks and waves. Six fast-forward shocks and, at least, two reverse waves were observed in the period of the two superstorms. A detailed analysis of these complex interplanetary features is performed in this work. 相似文献
19.
Coronal mass ejections (CMEs) and solar flares are the large-scale and most energetic eruptive phenomena in our solar system and able to release a large quantity of plasma and magnetic flux from the solar atmosphere into the solar wind. When these high-speed magnetized plasmas along with the energetic particles arrive at the Earth, they may interact with the magnetosphere and ionosphere, and seriously affect the safety of human high-tech activities in outer space. The travel time of a CME to 1 AU is about 1–3 days, while energetic particles from the eruptions arrive even earlier. An efficient forecast of these phenomena therefore requires a clear detection of CMEs/flares at the stage as early as possible. To estimate the possibility of an eruption leading to a CME/flare, we need to elucidate some fundamental but elusive processes including in particular the origin and structures of CMEs/flares. Understanding these processes can not only improve the prediction of the occurrence of CMEs/flares and their effects on geospace and the heliosphere but also help understand the mass ejections and flares on other solar-type stars. The main purpose of this review is to address the origin and early structures of CMEs/flares, from multi-wavelength observational perspective. First of all, we start with the ongoing debate of whether the pre-eruptive configuration, i.e., a helical magnetic flux rope (MFR), of CMEs/flares exists before the eruption and then emphatically introduce observational manifestations of the MFR. Secondly, we elaborate on the possible formation mechanisms of the MFR through distinct ways. Thirdly, we discuss the initiation of the MFR and associated dynamics during its evolution toward the CME/flare. Finally, we come to some conclusions and put forward some prospects in the future. 相似文献