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Science China Earth Sciences 2015年第7期58卷 1235-1242页

作者： WANG Juan DU AiMin zhang Ying zhang tielong GE YaSong State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Space Research Institute Austrian Academy of Sciences

We present a newly developed global magnetohydrodynamic(MHD) model to study the responses of the Earth's magnetosphere to the solar wind. The model is established by using the space-time conservation element and solution element(CESE) method in general curvilinear coordinates on a six-component grid system. As a preliminary study, this paper is to present the model's numerical results of the quasi-steady state and the dynamics of the Earth's magnetosphere under steady solar wind flow with due northward interplanetary magnetic field(IMF). The model results are found to be in good agreement with those published by other numerical magnetospheric models.

关键词： numerical simulation magnetosphere magnetohydrodynamic model adaptive mesh refinement technique the space-time conservation element and solution element method

Statistical study of magnetic holes in the upstream region of Mercury’s bow shock

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Earth and Planetary Physics 2024年第2期8卷 326-337页

作者： GuoQiang Wang SuDong Xiao MingYu Wu YuanQiang Chen tielong zhang Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen 518055China Shenzhen Key Laboratory of Numerical Prediction for Space Storm Harbin Institute of TechnologyShenzhen 518055China Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Space Research Institute Austrian Academy of SciencesGrazAustria

Magnetic holes are magnetic depression structures that exist widely in many plasma *** magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the properties of the magnetic holes with shorter durations are still ***,we investigate the magnetic holes with durations of 0.1-100 s in the upstream region of Mercury’s bow shock based on observations by the MESSENGER(MErcury Surface,Space ENvironment,GEochemistry,and Ranging)*** can be divided into two groups according to the distribution of their duration:small-duration magnetic holes(SDMHs,0.6 s).The duration of each group approximately obeys a log-normal distribution with a median of~0.25 s and 3 s,*** 1.7%(32.6%)of the SDMHs(LDMHs)reduce the magnetic field strength by more than 50%.For both groups,some structures have a linear or quasi-linear polarization,whereas others have an elliptical *** magnetic hole events in both groups tend to have a higher rate of occurrence when the interplanetary magnetic field strength is *** occurrence rates are also affected by Mercury’s foreshock,which can increase(decrease)the occurrence rate of the SDMHs(LDMHs).This finding suggests that Mercury’s foreshock might be one source of the SDMHs and that the foreshock can destroy some *** observations suggest that a new group of magnetic holes with durations of<0.6 s exist in the upstream region of Mercury’s bow shock.

关键词： magnetic hole solar wind Mercury foreshock

Statistics of the Interplanetary Magnetic Fields Observed at 0.72 AU and 1 AU

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空间科学学报 2010年第4期30卷 356-361页

作者： Li Xiaoyu zhang tielong State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences China Space Research Institute Austria Academy of Sciences Graz Austria

This paper presents the Interplanetary Magnetic Field (IMF) observations at 0.72 AU measured by Venus Express (VEX) and 1 AU by Advanced Composition Explorer (ACE) in *** distributions of daily averages of B are lognormal in both *** multiscale structure of the magnetic field fluctuations was described by studying the increments of B over a range scales from 10 min to 21.3 *** the Probability Distribution Functions (PDFs) can be described quantitatively by Tsallis distribution *** the ecliptic plane from 0.72 AU to 1 AU,the entropy index q increases with distance over all scales,indicating the intermittency of turbulence is *** widths of the PDFs at 0.72 AU are larger than those at 1 AU at all scales,which indicating the turbulence at 0.72 AU is more intense than that at 1 *** helps us understand the nature and development of the magnetic field fluctuations.

关键词：行星际磁场概率分布函数统计对数正态分布多尺度结构 PDF格式 PDF文件定量描述

Scalings for the Alfvén-cyclotron instability in a bi-kappa plasma

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Earth and Planetary Physics 2023年第6期7卷 631-639页

作者： YueQun Lou Xing Cao MingYu Wu BinBin Ni tielong zhang Shenzhen Key Laboratory of Numerical Prediction for Space Storm Institute of Space Science and Applied TechnologyHarbin Institute of TechnologyShenzhen 518055China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Space Research Institute Austrian Academy of SciencesGraz 8042Austria

The particle velocity distribution in space plasma usually exhibits a non-Maxwellian high-energy tail that can be well modeled by kappa *** this study,we focus on the growth rates of the Alfvén-cyclotron instability driven by ion temperature anisotropy in a kappa *** solving the kinetic linear dispersion equation,we explore the sensitivity of growth rates to the spectral indexκof a bi-kappa distribution under different plasma conditions,including a variety of plasma beta β_(hp) and temperature anisotropy A_(hp) values of hot ***,a concise,analytic scaling formula is derived that relates the dimensionless maximum growth rate to three independent variables:the spectral index and the plasma beta and temperature anisotropy of hot *** results show that as theκ-value increases,the instability bandwidth narrows and the maximum growth rate increases *** higherβ_(hp)and A_(hp)′the maximum instability undergoes a sharp increase as *** our fits of dimensionless maximum growth rates are compared with solutions to kinetic linear dispersion theory,the results generally exhibit good agreement between *** under the circumstances of largeκ-values and highβ_(hp)and A_(hp)′the scalings of maximum growth rates primarily accurately model the numerical *** analytic expressions can readily be used in large-scale models of the Earth’s magnetosphere to understand wave generation due to the Alfvén-cyclotron instability.

关键词： Alfvén-cyclotron instability kappa distribution kinetic linear dispersion theory scaling formula

Theoretical Study on Ion Escape in Martian Atmosphere

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Chinese Physics Letters 2007年第1期24卷 298-301页

作者：史建魁刘振兴 Klaus TORKAR tielong zhang State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 Space Research Institute Austrian Academy of Sciences A-8042 Graz Austria

Based on the observation that Martian magnetic moment is gradually reducing from the ancient to the present, we investigate the O^＋ ion flux distribution along magnetic field lines and the ion escaping flux in Martian tail with different assumed Martian magnetic moments. The results show that the O^＋ ion flux along magnetic field lines decreases with distance from Mars; the ion flux along the field line decreases more quickly if the magnetic moment is larger; the larger the magnetic moment, the smaller the ion escaping flux in the Martian tail. The ion escaping flux depends on Z-coordinate in the Martian tail. With decrease of the magnetic moment, the ion escaping flux in the Martian tail increases. The results are significant for studying the water loss from Mars S uFface.

关键词： Mars surface Mars atmosphere Mars Mars magnetic field Ion fluxes Magnetic fields Ion escape

Responses of the field-aligned currents in the plasma sheet boundary layer to a geomagnetic storm

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Earth and Planetary Physics 2023年第5期7卷 558-564页

作者： YuanQiang Chen MingYu Wu YangJun Chen SuDong Xiao GuoQiang Wang tielong zhang Shenzhen Key Laboratory of Numerical Prediction for Space Storm Harbin Institute of TechnologyShenzhen 518055China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Chinese Academy of Sciences Center for Excellence in Comparative PlanetologyHefei 230026China Space Research Institute Austrian Academy of SciencesGraz 8042Austria

Geomagnetic storms can result in large magnetic field disturbances and intense currents in the magnetosphere and even on the *** an important medium of momentum and energy transport among the solar wind,magnetosphere,and ionosphere,field-aligned currents(FACs)can also be strengthened in storm *** study shows the responses of FACs in the plasma sheet boundary layer(PSBL)observed by the Magnetospheric Multiscale(MMS)spacecraft in different phases of a large storm that lasted from May 27,2017,to May 29,*** of the FACs were carried by electrons,and several FACs in the storm time also contained sufficient ion *** FAC magnitudes were larger in the storm than in the quiet period,and those in the main phase were the *** this case,the direction of the FACs in the main phase showed no preference for tailward or earthward,whereas the direction of the FACs in the recovery phase was mostly *** results suggest that the FACs in the PSBL are closely related to the storm and could be driven by activities in the tail region,where the energy transported from the solar wind to the magnetosphere is stored and released as the storm is ***,the FACs are an important medium of energy transport between the tail and the ionosphere,and the PSBL is a significant magnetosphere–ionosphere coupling region in the nightside.

关键词： field-aligned currents plasma sheet boundary layer geomagnetic storm

Turbulence in the near-Venusian space: Venus Express observations

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Earth and Planetary Physics 2020年第1期4卷 82-87页

作者： SuDong Xiao MingYu Wu GuoQiang Wang Geng Wang YuanQiang Chen tielong zhang Harbin Institute of Technology Shenzhen 518055China Space Science Institute Macao University of Science and TechnologyMacao 999078China Chinese Academy of Sciences Key Laboratory of Geospace Environment University of Science and Technology of ChinaHefei 230026China Space Research Institute Austrian Academy of SciencesGraz 8042Austria

With Venus Express magnetic field measurements at 32 Hz from 2006 to 2012, we investigate statistically the magnetic fluctuations in the near-Venusian space. The global spatial distribution of their spectral scaling features is presented in MHD and kinetic regimes. It can be observed that turbulence is a common phenomenon in the solar wind in both regimes. The solar wind MHD turbulence is modified at the Venusian bow shock;MHD turbulence is absent in the Venusian magnetosheath but present at the magnetosheath boundary layer. Pre-existing kinetic turbulence from the far upstream solar wind is modified in the near solar wind region, while kinetic turbulence can be extensively observed throughout the Venusian magnetosheath and in some regions of the induced magnetosphere. Our results reveal that, in the near-Venusian space, energy cascade can be developed at the boundary between magnetosheath and wake, and the turbulence-related dissipation of magnetic energy occurs extensively in the magnetosheath and the induced magnetosphere.

关键词： turbulence near-Venusian space kinetic effects Venus Express

A high resolution lithospheric magnetic field model over China

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Science China Earth Sciences 2013年第10期56卷 1759-1768页

作者： OU JiaMing DU AiMin E.THBAULT XU WenYao TIAN XiaoBo zhang tielong Institute of Geology and Geophysics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Equipe de Géomagnétisme Institut de Physique du Globe de ParisSorbonne 4 Paris CitéINSU/CNRS1 rue Jussieu75005 ParisFrance Space Research Institute Austrian Academy of Sciences

CHAMP satellite data and ground-based magnetic observations are used and combined to map the lithospheric magnetic field over China by means of the revised spherical cap harmonic analysis(R-SHCA)modeling *** magnetic field is described to a spatial resolution of 150 km at the mean Earth’s radius,which represents a good compromise between the resolutions afforded by surface and satellite *** compare the magnetic anomalies modeled at the regional scale with composite regions containing large-scale of tectonic *** regions,including the Tarim Basin and the Tibetan Plateau,are correlated with regional magnetic anomalies at satellite altitude but contain a significant number of small-scale and complex magnetic structures at the mean Earth’s *** magnetic anomalies are globally consistent with the known geological features in China but also offer a way to delineate the contours of the geological blocks and to discuss the connection between magnetic anomalies and the heat flow distribution in this region.

关键词： lithospheric magnetic field revised spherical harmonic cap analysis CHAMP satellite data

Comparison between magnetic coplanarity and MVA methods in determining the normal of Venusian bow shock

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Chinese Science Bulletin 2013年第20期58卷 2469-2472页

作者： SHAN LiCan LU QuanMing zhang tielong GAO XinLiang HUANG Can SU YanQing WANG Shui CAS Key Laboratory of Basic Plasma Physics Department of Geophysics and Planetary Science University of Science and Technology of China

With the measurements of magnetic field of Venus Express (VEX), magnetic coplanarity and minimum variance analysis (MVA) methods are analyzed and their validity is tested to determine the normal of Venusian bow shocks. It is found that MVA method is the better than magnetic coplanarity, and 95% shock crossings can be accurately determined by the method. However, the occurrence of the shock normal which is not determined accurately by magnetic coplanarity increases with the decrease of the solar zenith angle (SZA). At the same time, compared with quasi-parallel shocks, there is more occurrence of the shock normal which cannot be determined accurately by magnetic coplanarity for quasi-perpendicular shocks.

关键词：共面性 MVA 金星激波定正太阳天顶角测量方法方差分析

Ablation of Venusian oxygen ions by unshocked solar wind

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Science Bulletin 2017年第24期62卷 1669-1672页

作者： Yong Wei Markus Fraenz Edward Dubinin Weixing Wan tielong zhang Zhaojin Rong Lihui Chai Jun Zhong Rixiang Zhu Yoshifumi Futaana Stas Barabash Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Max-Planck-lnstitute for Solar System Research Goettingen 37077 Germany Space Research Institute Austrian Academy of Sdences Graz 8042 Austria Swedish Institute of Space Physics Kiruna SE-981 28 Sweden College of Earth Sciences University of Chinese Academy of Sciences Beijing 100049 China Institutions of Earth Science Chinese Academy of Sciences BeUing 100029 China

As an Earth-like planet Venus probably had a primordial dipole field for several million years after formation of the *** this dipole field eventually vanished the ionosphere of Venus has been exposed to the solar *** solar wind is shocked near Venus,and then scavenges the ionospheric particles through the magnetosheath and the *** escape rate of oxygen ions(O^+)estimated from spacecraft observations over the past several decades has manifested its importance for the evolution of planetary habitability,considering the accumulated effect over the history of ***,all the previous observations were made in the shocked solar wind and/or inside the wake,though some simulations showed that unshocked solar wind can also ablate O^+*** we report Venus Express observations of O^+ions in the unshocked solar wind during the solar *** observations suggest that these O^+ions are accelerated by the unshocked solar wind through pickup *** estimated O^+escape rate,2.1×10^(24) ions/s,is comparable to those measured in the shocked solar wind and the *** escape rate could result in about 2 cm global water loss over 4.5 billion *** results suggest that the atmospheric loss at unmagnetized planets is significantly underestimated by previous observations,and thus we can emphasize the importance of an Earth-like dipole for planetary habitability.

关键词： Venus Ion escape Planetary habitability