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An empirical model of the global distribution of plasmaspheric hiss based on van allen probes EMFISIS measurements

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Earth and Planetary Physics 2020年第3期4卷 246-265页

作者： JingZhi Wang Qi Zhu XuDong Gu Song Fu JianGuang Guo XiaoXin Zhang Juan Yi YingJie Guo BinBin Ni Zheng Xiang Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430079China Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing 100081China

Using wave measurements from the EMFISIS instrument onboard van allen probes,we investigate statistically the spatial distributions of the intensity of plasmaspheric hiss *** reproduce these empirical results,we establish a fitting model that is a thirdorder polynomial function of L-shell,magnetic local time(MLT),magnetic latitude(MLAT),and AE*.Quantitative comparisons indicate that the model’s fitting functions can reflect favorably the major empirical features of the global distribution of hiss wave intensity,including substorm dependence and the MLT *** results therefore provide a useful analytic model that can be readily employed in future simulations of global radiation belt electron dynamics under the impact of plasmaspheric hiss waves in geospace.

关键词： hiss van allen probes global model

地球磁暴期间辐射带能量电子通量变化的统计研究：van allen probes卫星观测

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地球磁暴期间辐射带能量电子通量变化的统计研究：Van Allen Prob...

作者：余德银南昌大学

学位级别：硕士

地球辐射带是近地空间的重要圈层之一,与磁层和电离层等其他区域会发生许多耦合作用,航天器的通信和运行也常常受到辐射带环境的高度影响,因此对日地空间环境和空间天气预报具有非常重要的研究意义,引起了空间物理学家们的广泛关注,成... 详细信息

地球辐射带是近地空间的重要圈层之一,与磁层和电离层等其他区域会发生许多耦合作用,航天器的通信和运行也常常受到辐射带环境的高度影响,因此对日地空间环境和空间天气预报具有非常重要的研究意义,引起了空间物理学家们的广泛关注,成为空间物理研究的热点之一。几十年来,人类发射了许多卫星去测量辐射带各个方面的物理特性,为空间探测、载人航天和卫星通信应用等提供更准确更详细的现报和预报。2012年8月,美国NASA成功发射了van allen probes卫星,对地球辐射带在不同时间和空间尺度上的动态过程和对近地空间环境的影响,进行了长时间和多点观测,积累了大量有效观测数据,对辐射带粒子动力学过程和动态变化的研究进一步深入,为辐射带观测研究和理论建模提供了很好的机遇。在辐射带能量电子通量变化研究中,Summers、Fox以及Mauk等人在理论研究方面取得了一系列原创性的进展。Mauk et al.(2010)中提出了强磁化行星(地球、土星、木星、天王星、海王星)都具有类辐射带结构,并通过观测数据发现,部分区域的能量电子差分通量都存在类似“拐点”的现象,并给出了相应的理论模型。如地球辐射带,L=4、5和6时,其电子通量变化往往会出现“拐点”,但是也存在着很多不同之处。为了更好的了解辐射带的动态变化,我们利用van allen probes观测数据,对典型磁暴期间辐射带能量电子通量的变化特征进行细致分析和统计研究。我们选取了2012年到2015年期间的三个典型磁暴事件,对事件中van allen probes的磁电子离子谱仪(MagEIS)和相对论质子望远镜(REPT)仪器观测的能量电子数据进行数据分析。(1)首先我们选择对典型磁暴期间的能量电子通量在磁暴发生前后和不同L-shell进行统计研究。结果表明,磁暴期间各L-Shell上的能量电子通量均会出现程度不同的变化。L=2区域的电子通量相对较为稳定,磁暴环境对其通量的改变在很小的范围内波动;L=3、4、5、6区域的电子通量会随着磁暴环境的影响而存在较大的变化,随着磁暴强度的不同变化的程度也会不同。L=3时,高能电子通量处于较低水平,强磁暴环境下的中等能级电子通量能最高提升10倍;L=4时,在平静期,电子通量会在中等能级处出现极小值,通量曲线形如“凹槽”,磁暴响应下使得低能电子通量衰减的速率呈现1/E形态;L=5和L=6时,低能电子通量都会出现形如1/E的衰减,衰减速率随L值增大而增大,高能电子通量下降速率很快。辐射带的位置并不是永恒不变的,随着磁暴的发生,辐射带的边界会向内侵蚀,从而改变各L-Shell相对于的辐射带的位置。另外,在外辐射带区域的能量电子通量确实存在“拐点”现象。(2)磁暴会伴随着亚暴的发生,当AE指数较大时,VAP卫星的通量观测曲线有较大的差别。我们针对三个典型磁暴期间的亚暴事件展开研究,首先对2013年3月17日至30日期间AE指数较大的时间段进一步分析,试图找寻这种差别与MLT或者AE、DST之间是否存在进一步的联系。发现能量电子差分通量形式下的电子通量变化与MLT之间的关系没有很明显的体现,但是较大的DST会导致给定L-Shell时的低中能电子通量存在明显差异。因此,我们计划在后续工作中通过将能量电子差分通量转换成全向粒子积分通量来解决这一问题。(3)为了进一步研究电子通量变化中能量“拐点”的情况,我们采用最小二乘法对电子通量观测数据进行拟合,验证了拟合结果并讨论了误差大小。经过对三个磁暴事件拟合结果的仔细分析,我们发现:参数C的范围在10-10区间内,L=5时会出现最小为10的结果;参数E0在1500-2500keV之间,上下限略有浮动;参数γ1处在1之间,且L=6区域的值整体上会比L=5时的要大,且L=5会出现在0.5之间的结果;参数γ2平稳的在6之间变动。并存在参数C和γ1与DST之间存在正向相关性。结果表明,在L=4,5,6时能量电子差分通量变化的拐点的确存在,但是并不固定,参数E0是表征拐点所处能级的大小,依照参数E0的结果,拐点将在1500500keV范围内变化。本文的统计分析结果对辐射带电子通量理论建模和未来辐射带电子环境变化的预报现报等都具有很重要的研究意义。

关键词：地球辐射带磁暴亚暴能量电子通量变化 van allen probes

亚暴注入锋面的径向传播:基于BD-IES和van allen probes的统计研究

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亚暴注入锋面的径向传播:基于BD-IES和Van Allen Probes的统计研究

Generation of simultaneous H^(+)and He^(+)band EMIC waves in the nightside radiation belt

2017中国地球科学联合学术年会

作者：刘志扬宗秋刚郝以鑫周煦之北京大学地球与空间科学学院

利用多颗卫星对亚暴注入事件进行观测,有助于理解亚暴注入的可能的机制。在本研究中,利用搭载于倾斜同步轨道(IGSO)卫星上的BD-IES获得的电子通量数据,以及转移轨道(GTO)卫星van allen probes(A和B)获得的数据,我们对亚暴注入进行了统... 详细信息

利用多颗卫星对亚暴注入事件进行观测,有助于理解亚暴注入的可能的机制。在本研究中,利用搭载于倾斜同步轨道(IGSO)卫星上的BD-IES获得的电子通量数据,以及转移轨道(GTO)卫星van allen probes(A和B)获得的数据,我们对亚暴注入进行了统计研究。总共有64个注入事件被挑选出来,每个注入事件均被BD-IES和van allen probes观测到。在研究中我们发现,一次注入事件可

关键词： BD-IES 统计研究 van allen probes

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Science China(Technological Sciences) 2020年第11期63卷 2369-2374页

作者： GUAN ChunYi SHANG XiongJun XIE YanQiong YANG Chang ZHANG Sai LIU Si XIAO FuLiang School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China

Previous studies have shown that EMIC waves occur preferentially in the afternoon sector of the *** we report obliquely propagating H^(+)and He^(+)band EMIC waves detected by van allen Probe B in the region of MLT=22.7–23.5 during the June 20,2013 *** the correlated energetic proton data,we present continuous calculations on EMIC wave growth rates along the inward orbit in the region L=5.5–*** modeled growth rate shows remarkable agreement with the observed double band EMIC waves in both temporal and spatial *** current results demonstrate that H^(+)and He^(+)band EMIC waves can be simultaneously excited in the midnight sector under appropriate conditions.

关键词： EMIC waves instability nightside radiation belt van allen probes coordinated observations

Numerical simulation of chorus-driving acceleration of relativistic electrons at extremely low L-shell during geomagnetic storms

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Chinese Physics B 2021年第10期30卷 711-718页

作者： Zhen-Xia Zhang Ruo-Xian Zhou Man Hua Xin-Qiao Li Bin-Bin Ni Ju-Tao Yang National Institute of Natural Hazards MEMCBeijing 100085China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China

During 2018 major geomagnetic storm,relativistic electron enhancements in extremely low L-shell regions(reaching L∼3)have been reported based on observations of ZH-1 and van allen probes satellites,and the storm is highly likely to be accelerated by strong whistler-mode waves occurring near very low L-shell regions where the plasmapause was *** is very interesting to observe the intense chorus-accelerated electrons locating in such low L-shells and filling into the slot *** this paper,we further perform numerical simulation by solving the two-dimensional Fokker-Planck equation based on the bounce-averaged diffusion *** results demonstrate the evolution processes of the chorus-driven electron flux and confirm the flux enhancement in low pitch angle ranges(20◦-50◦)after the wave-particle interaction for tens of *** simulation result is consistent with the observation of potential butterfly pitch angle distributions of relativistic electrons from both ZH-1 and van allen probes.

关键词： chorus acceleration extremely low L-shell numerical simulation ZH-1 satellite van allen probes

The 600 keV electron injections in the Earth's outer radiation belt:A statistical study

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Earth and Planetary Physics 2022年第2期6卷 149-160页

作者： ChaoLing Tang Xu Wang BinBin Ni ZhengPeng Su JiChun Zhang Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai Shandong 264209China School of Space Science and Physics Shandong UniversityWeihai Shandong 264209China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China CAS Center for Excellence in Comparative Planetology Hefei 230026China CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China Staunch Data Analytics Lab DurhamNew HampshireUSA

Relativistic electron injections are one of the mechanisms of relativistic(≥0.5 MeV) electron enhancements in the Earth’s outer radiation belt. In this study, we present a statistical observation of 600 keV electron injections in the outer radiation belt by using data from the van allen probes. On the basis of the characteristics of different injections, 600 keV electron injections in the outer radiation belt were divided into pulsed electron injections and nonpulsed electron injections. The 600 keV electron injections were observed at 4.5 < L <6.4 under the geomagnetic conditions of 450 nT < AE < 1,450 nT. An L of ~4.5 is an inward limit for 600 keV electron injections. Before the electron injections, a flux negative L shell gradient for ≤0.6 MeV electrons or low electron fluxes in the injected region were observed. For600 keV electron injections at different L shells, the source populations from the Earth’s plasma sheet were different. For 600 keV electron injections at higher L shells, the source populations were higher energy electrons(~200 keV at X ~–9 R_(E)), whereas the source populations for 600 keV electron injections at lower L shells were lower energy electrons(~80 keV at X ~–9 R_(E)). These results are important to further our understanding of electron injections and rapid enhancements of 600 keV electrons in the Earth’s outer radiation belt.

关键词： electron injections relativistic electrons the Earth’s outer radiation belt plasma sheet van allen probes