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太阳风在地球激波前兆区减速的统计研究

地球物理学报 2009年第4期52卷 895-901页

作者：符慧山曹晋滨张铁龙 H.Reme e.lucek 中国科学院空间天气学国家重点实验室北京100080 中国科学院研究生院北京100049 Space Research Institute Austrian Academy of Sciences8042 GrazAustria Centre d'etude Spatiale des Rayonnements 31028ToulouseFrance The Blackett Laboratory Imperial CollegeLondonSW7 2BZUnited Kingdom

本文首次利用完全相同两颗卫星(CLUSTeR C1和C3)的数据对地球激波前兆区太阳风的减速和偏转特性进行了统计研究.结果表明,在激波前兆坐标系中,太阳风减小的速度随观测点到激波的距离D_(BS)增大而减小,随行星际磁场与激波法向夹角θ_(BN... 详细信息

本文首次利用完全相同两颗卫星(CLUSTeR C1和C3)的数据对地球激波前兆区太阳风的减速和偏转特性进行了统计研究.结果表明,在激波前兆坐标系中,太阳风减小的速度随观测点到激波的距离D_(BS)增大而减小,随行星际磁场与激波法向夹角θ_(BN)增大也减小,在ULF波动区深度D_(WS)小于6R_e(R_e为地球半径)的范围内最为显著;伴随着太阳风减速的另外一个现象——太阳风的偏转,也存在相似的规律.其最大减速和最大偏转角度分别为10 km/s和3°.太阳风减速和偏转,以及随之变化的太阳风动压,可能会引起地球磁层顶位置和形状发生改变,同时也为激波前兆区弥散(diffuse)离子的起源及加热提供了一种可能的机制.

关键词：相同卫星太阳风减速太阳风偏转激波前兆坐标系

Statistical survey on the magnetic structure in magnetotail current sheets

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Statistical survey on the magnetic structure in magnetotail ...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： M.W.Dunlop A.A.Petrukovich e.lucek Rutherford Appleton Laboratory Didcot UK Space Research Institute Moscow Russia Blackett Laboratory Imperial College London LondonUK

[1]On the basis of the multipoint magnetic observations of Cluster in the region 15-19 R downtail,the magnetic field structure in magnetotail current sheet(CS) center is statistically *** is found that the B component(in GSM coordinates) is distributed mainly within |B|e the B component is mostly positive and distributes mainly within 10 *** plane of the magnetic field lines(MFLs) is mostly vertical to the equatorial plane,with the radius of curvature(Rc) of the MFLs being directed earthward and the binormal(perpendicular to the curvature and magnetic field direction) being directed azimuthally *** curvature radius of MFLs reaches a minimum,R,at the CS center and is larger than the corresponding local half thickness of the neutral sheet,h. Statistically,it is found that the overall surface of the CS,with the normal pointing basically along the south-north direction,can be approximated to be a plane parallel to equatorial plane,although the local CS may be flapping and is frequently tilted to the equatorial *** tilted CS(normal inclined to the equatorial plane) is apt to be observed near both flanks and is mainly associated with the slippage of magnetic flux *** is statistically verified that the minimum curvature radius,R,half thickness of neutral sheet,h,and the slipping angle of MFLs,8,in the CS satisfies h = R cosδ.The current density,with a mean strength of 4-8 nA/m,basically flows azimuthally and tangentially to the surface of the CS,from dawn side to the dusk *** is an obvious dawn-dusk asymmetry of CS,*** magnetic local times(MLT) 1:00-～01:00, the CS is relatively thinner;the minimum curvature radius of MFLs,R(0.6-1 R) and the half-thickness of neutral sheet,h(0.2-0.4 R),are relatively smaller,and B(3-5 nT) and the minimum magnetic field,B(5-7 nT),are *** is also found that negative B has a higher probability of occurrence and the cross-tail current density j is dominant (2-4 nA/m) in comparison to

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Cluster and TC-1 observation of magnetic holes in the plasma sheet

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Cluster and TC-1 observation of magnetic holes in the plasma...

第十四届全国日地空间物理学术研讨会

作者： M.W.Dunlop A.P.Walsh H.Reme C.Carr e.lucek A.Fazakerley Rutherford Appleton Laboratory Didcot OX11 0QX UK Mullard Space Science Laboratory University College London Holmbury St.Mary Dorking Surrey RH5 6NT UK Université de Toulouse

Magnetic holes with relatively small scale sizes, detected by Cluster and TC-1 in the magnetotail plasma sheet, are studied in this paper. It is found that these magnetic holes are spatial structures and they are not magnetic depressions generated by the flapping movement of the magnetotail current sheet. Most of the magnetic holes (93%) were observed during intervals with B z larger than B x, i.e., they are more likely to occur in a dipolarized magnetic field topology. For the randomly selected plasma sheet crossing events there are only 31% of the cases have the magnetic field with Bz larger than Bx, suggesting that the occurrence of magnetic holes might have a close relationship with the dipolarization process and/or a perturbed magnetosphere. The magnetic holes typically have a scale size comparable to the local proton Larmor radius and are accompanied by an electron flux enhancement at 90°pitch angle. It is also shown that most of the magnetic holes occur in the marginally mirror-stable environments;however, whether the plasma sheet magnetic holes are generated by the mirror instability related to ions or not is unknown. Comparison of ratios, scale sizes and propagation direction of magnetic holes detected by Cluster and TC-1 suggests that magnetic holes observed in the vicinity of TC-1 orbit (-12Re) are likely further developed than those observed by Cluster (-18Re).

关键词： magnetic holes mirror mode structures plasma sheet dipolarization

Cluster卫星对磁尾电流片运动特性的统计分析

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中国科学：技术科学 2010年第7期40卷 757-764页

作者：孙为杰史全岐傅绥燕宗秋刚濮祖荫谢伦肖婷李蕾刘振兴 H.Reme e.lucek 山东大学威海分校空间科学与物理学院威海264209 中国科学院空间天气学国家重点实验室(中国科学院空间科学与应用研究中心) 北京100080 北京大学地球与空间科学学院北京100871 Centre D’etude Spatiale des Rayonnements University Paul Sabatier University of Toulouse ToulouseFrance UMR5187 CNRSToulouseFrance Space and Atmospheric Physics Group Blackett LaboratoryImperial CollegeLondonUK

地球磁尾电流片拍动的起源和运动方式一直是磁尾动力学研究中的重要问题之一.本文利用Cluster卫星数据,统计分析了2001年和2003年的磁尾电流片运动特性,利用我们最近发展的分析结构特征方向和运动速度的新方法,计算了磁尾电流片的运动速... 详细信息

地球磁尾电流片拍动的起源和运动方式一直是磁尾动力学研究中的重要问题之一.本文利用Cluster卫星数据,统计分析了2001年和2003年的磁尾电流片运动特性,利用我们最近发展的分析结构特征方向和运动速度的新方法,计算了磁尾电流片的运动速度,并给出了磁尾电流片在GSe坐标系中XY平面内的速度分布图.我们发现磁尾电流片存在着两种不同性质的运动,除了磁尾电流片向晨昏方向的运动,分析表明,磁尾电流片还存在着明显朝向子夜方向的运动(即GSe坐标系中Y=0平面).观测还进一步表明,位于磁尾中间区域(|Y_GSe|e)的电流片的扰动,其南北向的速度分量相对较大,这从另一个方面说明磁尾中性片的中间区域可能是导致大部分磁尾电流片拍动事件中电流片朝向晨昏两侧运动的源区.对于运动方向朝向子夜方向(Y=0平面)的电流片,其运动方式与运动方向朝向晨昏两侧的电流片存在着明显的不同,因此我们推测,它们应具有不同的起源.本文的统计结果,为我们深入研究地球磁尾电流片拍动源区等物理问题提供了的参考依据.

关键词：磁尾电流片拍动源区

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磁层快速对流事件的多点卫星联合观测

地球物理学报 2007年第5期50卷 1277-1282页

作者：马玉端曹晋滨周国成刘振兴 H. Reme I. Dandouras e. lucek 中国科学院空间天气学重点实验室北京100080 Centre d'etude Spatiale des Rayonnements Imperial College London

本文利用星簇Cluster的三颗卫星(C1,C3和C4)在2001年和2002年的数据,研究了快速对流事件(RCe,Rapid Convection event)及其与亚暴的关系.结果显示单点卫星对RCe的观测,不能反映磁尾RCe的真实情况.在2002年7月25日发生的一次RCe事件,C1... 详细信息

本文利用星簇Cluster的三颗卫星(C1,C3和C4)在2001年和2002年的数据,研究了快速对流事件(RCe,Rapid Convection event)及其与亚暴的关系.结果显示单点卫星对RCe的观测,不能反映磁尾RCe的真实情况.在2002年7月25日发生的一次RCe事件,C1和C3观测到这次RCe,C4却没有观测到.在三颗卫星联合观测到的306次RCe中,C1观测到215次,C3观测到266次,C4观测到227次.统计研究表明,单点卫星观测到的RCe的平均时间也不能准确反映磁层内的RCe.由此推论在整个中心等离子体片内,快速对流事件所承担的能量和磁通量的输运量,可能远大于单点卫星观测给出的结果.用速度来定义的磁尾爆发性整体流(BBF,Bursty Bulk Flow)与亚暴的关系,比用磁通量定义的RCe与亚暴的关系要更加紧密.

关键词： RCe 磁通量持续时间输运

极尖区电离层离子与地磁活动及太阳风的相关分析

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科学通报 2007年第3期52卷 339-343页

作者：郭建广史建魁 T.L.Zhang 刘振兴 A.Fazakerley H.Rème I.Dandouras e.lucek 中国科学院空间天气学国家重点实验室 Space Research Institute Aus-trian Academy of SciencesGrazA-8010 Austria Mullard Space Science Laboratory University College LondonHolmbury St.MaryDorking RH5 6NTUK Centred'etude Spatiale des Rayonnements Toulouse 31028France Imperial College LondonS 272B2UK

对2001～2003年间Cluster星簇穿越极尖区期间观测到的电离层起源的离子(O+离子,He+离子和H+离子)特性进行了统计分析,主要研究了这些离子的数密度与地磁活动以及太阳风动压之间的关系.结果表明:O+离子数密度和地磁活动指数Kp之间存在着... 详细信息

对2001～2003年间Cluster星簇穿越极尖区期间观测到的电离层起源的离子(O+离子,He+离子和H+离子)特性进行了统计分析,主要研究了这些离子的数密度与地磁活动以及太阳风动压之间的关系.结果表明:O+离子数密度和地磁活动指数Kp之间存在着正相关关系,He+离子数密度和地磁活动指数Kp不相关,O+离子和He+离子数密度都和太阳风动压之间存在着显著的正相关关系;H+离子数密度与太阳风动压之间存在着正相关关系,而和地磁活动指数Kp不相关.最后,对这些离子的特性与太阳风动压及地磁活动之间的关系进行了讨论.

关键词：极尖区离子 Kp指数太阳风动压

THeMIS observations of two substorms on February 26,2008

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Science China(Technological Sciences) 2010年第5期53卷 1328-1337页

作者： CHU XiangNing PU ZuYin CAO Xin WANG Jue V.MISHIN V.ANGeLOPOULOS LIU Jiang WeI Yong K.H.GLASSMeIeR J.MCFADDeN D.LARSON S.MeNDe H.FReY C.T.RUSSeLL I.MANN D.SIBeCK ZONG QiuGang FU SuiYan XIe Lun T.I.SAIFUDINOVA M.V.TOLOCHKO L.A.SAPRONOVA H.ReMe e.lucek School of earth and Space Sciences Peking UriiversityBeijing 100871China Institute of Solar-Terrestrial Physics Russian Academy of Sciences IGPP UCLA Instiute of Geophysics and extraterrestrial Physics Technical University of BraunschweigBraunschweig and Max Planck Institute of Solar System Research Space Sciences Laboratory University of California Department of Physics University of Alberta Code 674 NASA/GSFC Centre d'etude Spatiale des Rayonnements Blackett Laboratory Imperial College London

Two substorms occurred at ～04:05 and ～04:55 UT on February 26,2008 are studied with the in-situ observations of THeMIS satellites and ground-based aurora and magnetic field *** et *** made a comprehensive study of the 04:55 UT *** showed detailed features of the two substorms with much attention to the first event and to the rela-tionship between mid-tail magnetic reconnection(MR) and substorm *** was found that in the earlier stage of each substorm,a first auroral intensification occurred 2-3 min soon after the start of mid-tail MR,followed by a slow and very lim-ited *** auroral arcs were weak,short-lived,and localized,characterizing all features of a *** re-garded the first auroral brightening as the initial onset of the substorms.A few minutes later,a second stronger auroral intensification appeared,followed by quick and extensive *** was interesting to note that the second brightening and related poleward expansion happened almost simultaneously(within a couple of minutes) with the onset of earthward flow and dipolarization in the near-earth tail and other phenomenon of the substorm expansion *** thus regarded the second auroral brightening as the major onset of the ***,it was seen that during the growth phase of the two substorms,the polar cap open flux Ψ kept increasing,while it quickly reduced during the substorm expansion and recovery *** variations of Ψ implied that the evolution of the two substorm expansion phases were closely related to MR of tail lobe open field *** of substorm activities revealed that the two events studied were small substorms;while estimate of MR rate indicated that the MR processes in the two substorms were *** aforementioned observations suggested that mid-tail MR initiated the pseudobreakup first;the earthward flow generated by MR transported magnetic flux and energy to the near-earth tail to cause the formatio

关键词： substorm auroral intensification/brightening auroral expansion dipolarization magnetic reconnection

MHD和动力学下联合分析一个亚暴膨胀相期间的等离子体流

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MHD和动力学下联合分析一个亚暴膨胀相期间的等离子体流

中国空间科学学会空间物理学专业委员会第十五届全国日地空间物理学研讨会

作者：马玉端曹晋滨 H.Reme I.Dandouras M.Dunlop e.lucek 北京航空航天大学宇航学院

结合地磁和太阳风数据,中磁尾Cluster的C1卫星和近地双星TC-1的等离子体和磁场观测数据,研究亚暴膨胀相期间地向流爆发在磁尾等离子体片的运动.联合使用MHD理论和动力学两种方法,发现地向流在近地和中磁尾的运动明显不同.从MHD的观点来...

结合地磁和太阳风数据,中磁尾Cluster的C1卫星和近地双星TC-1的等离子体和磁场观测数据,研究亚暴膨胀相期间地向流爆发在磁尾等离子体片的运动.联合使用MHD理论和动力学两种方法,发现地向流在近地和中磁尾的运动明显不同.从MHD的观点来看,近地的TC-1卫星先观测到了尾向流,然后是地向流与尾向流交替出现的过程.中磁尾的C1卫星先观测到地向等离子体流,然后是尾向流.中磁尾和近地卫星初始观测到地向等离子体流的当地熵,都明显的小于尾向流的.如果从动动力学角度来看,与使用MHD的结果相比:中磁尾的结果没有改变,近地卫星的结果却差别很大:(1)TC-1最初观测到尾向流时,并没有明显的高能量的尾向离子通量增强;(2)在地向流期间,能量超过10KeV地向离子通量的明显增强;(3)地向高速流之后,地向离子通量仍然明显增强,能量为1个10KeV,同时伴随此能量范围内的尾向、晨向和昏向离子通量的明显增强。综合MHD和动力学分析,我们认为近地等离子体流的运动过程类似于地向流过冲到近地被反弹后衰减振荡,并可能伴随有等离子体流的转向或者漩涡状结构.而中磁尾附近的等离子体流,却是简单地反弹为尾向流.

关键词：

Profile of strong magnetic field By component in magnetotail current sheets

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Profile of strong magnetic field By component in magnetotail...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Z.J.Rong W.X.Wan C.Shen X.Li M.W.Dunlop A.A.Petrukovich L.-N.Hau T.L.Zhang H.Reme A.M.Du e.lucek Beijing National Observatory of Space environment Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences Laboratory for Atmosphere and Space Physics Department of Aerospace and Engineering SciencesUniversity of Colorado at BoulderBoulderColoradoUSA. Rutherford Appleton Laboratory OxfordUK. Space Research Institute MoscowRussia. Institute of Space Science National Central UniversityJhongliTaiwan. Department of Geophysics and Planetary Sciences University of Science and Technology of ChinaHefeiChina Space Research Institute Austrian Academy of SciencesGrazAustria. IRAP University of ToulouseToulouseFrance.CNRSIRAPToulouseFrance. Blackett Laboratory Imperial College LondonLondonUK.

[1]The strong magnetic field B component(in GSM coordinates) has been increasingly noticed to play an important role in the dynamics of tail current sheet (CS).The distribution profile of strong B components in the ta...

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