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Science China Earth Sciences 2015年第5期58卷 830-838页

作者： ZHANG JingBo HE JianSen YAN LiMei tu chuanyi WANG LingHua WANG Xin Institute of Space Physics and Applied Technology Peking University

Using observations from the EUV Imaging Spectrometer （EIS） onboard Hinode, we exam the plasma dynamics around the edge of the active region 10977, possibly associated with the source of nascent slow/intermediate solar wind. The correlation between the temporal profiles of the radiation intensity and Doppler shift for each emission line are analyzed. And three small regions with positive correlations for all the five emission lines are selected for a detailed analysis. In this work, Doppler blue （red） shift is defined as negative （positive）. We find that in Region 1, the radiation intensity （Doppler velocity） decreases by about 15% （about 3 km s-X）, and logarithmical differential emission measures （lg（DEMs）） reduces by about 0.06-0.10% at all temperatures, called ＂weak dimming＂, during a 30-min interval. In Region 2 and Region 3, however, the radiation intensity （Doppler velocity） increases by about 15% （about 3 km s-l）, and lg（DEMs） increases by about 0.06%~0.10% at all tempera- tures, called ＂weak brightening＂. Such weak dimming （weak brightening） could reflect a slow draining （replenishing） of plas- ma in the solar wind flux tubes, possibly due to a larger （smaller） outflow flux at high altitude than at low altitude. These sug- gest that the plasma supply could be intermittent with an alternation of draining and replenishing, for which the underlying physical process is yet unknown, at the source region of slow/intermediate solar wind.

关键词： solar corona solar wind active region

Multi-scale pressure-balanced structures in the solar wind observed by WIND

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Chinese Science Bulletin 2012年第12期57卷 1421-1428页

作者： YAO Shuo tu chuanyi HE JianSen2 WEI WenBo MENG XiaoHong School of Geophysics and Information Technology China University of Geosciences （Beijing） Beijing 100083 China School of Earth and Space Sciences Peking University Beijing 100871 China

This work detects multi-scale, from hour to seconds, pressure-balanced structures (PBSs) in the solar wind based on the anti- correlation between the plasma thermal pressure and the magnetic pressure measured by WIND at 1 AU on April 5th, 2001. In our former research based on Cluster measurements, we showed the anti-correlation between the electron density and the magnetic field strength in multi-scales, and we supposed these structures may be pressure-balanced structures. Thus, in this work we aim to prove our speculation by the direct evidence on pressure measurements. Different from our previous work, we apply the WIND measurements this time, for they have both the magnetic pressure and the plasma pressure which Cluster could not offer. We use the wavelet cross-coherence method to analyze the correlation between the plasma pressure (P th ) and the magnetic pressure (P B ), and also the electron density (N e ) and the magnetic field strength (B) on various scales. We observe the anti-correlation between P th and P B distributed at different temporal scales ranging from 1000 s down to 10 s. This result directly indicates the existence of pressure- balanced structures (PBSs) with different sizes in the solar wind. Further, We compare the wavelet cross correlation spectrum of P th -P B and N e -B. We notice that the two spectra are similar in general. Thus this result confirms that the relation between P th -P B and N e -B are consistent with each other in the PBSs we study. Moreover, we compare the power spectrum density (PSD) of relative N e fluctuation with our previous work based on Cluster measurements. The two spectra show similar trend with Komolgorov's -5/3 as their slopes. This may imply the similarity of the structures observed by both WIND and Cluster spacecrafts. Finally, we discuss the possible formation mechanisms for these multi-scale pressure-balanced structures. Our result is important to support the existence of multi-scale PBSs from one-hour scale

关键词：多尺度结构压力平衡太阳风用户交换机压力测量等离子体压力平衡结构磁场强度

Discrete energetic(～50-200 keV) electron events in the high-altitude cusp/polar cap/lobe

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Science China(Technological Sciences) 2017年第12期60卷 1935-1940页

作者： WANG LingHua ZONG QiuGang SHI QuanQi WANG YongFu tu chuanyi HE JianSen TIAN Hui WIMMER-SCHWEINGRUBER Robert F. ZOU Hong Institute of Space Physics and Applied Technology Peking University Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsShandong University Institute for Experimental and Applied Physics University of Kiel

We identified 28 discrete electron events(DEEs) with enhanced fluxes at ~50-200 keV in the high-altitude cusp/polar cap/lobe,using the electron measurements by the BeiDa Image Electron Spectrometer(BD-IES) instrument onboard an inclined(55°)geosynchronous orbit(IGSO) satellite from October 2015 to January 2016. We find that among the 28 DEEs, 22 occur in the nightside and mostly in the northern cusp/polar cap/lobe, while 6 occur in the dayside and all in the southern cusp; 24 events correspond to an average interplanetary magnetic field(IMF) component B_z>0, 3 correspond to an average IMF B_ztude from event to event. The spectral index of these cusp DEEs are(strongly) larger than the spectral index of solar wind superhalo electrons(radiation belt electrons) observed by the WIND 3 D Plasma & Energetic Particle instrument(the BD-IES). At^110 keV,the electron flux of DEEs in the cusp/polar cap/lobe shows a weak positive correlation with the solar wind superhalo electron flux but no obvious correlation with the radiation belt electron flux. These results suggest that these DEEs probably originate from transient processes acting on the solar wind superhalo electrons, e.g., the mid/high-latitude reconnection.

关键词： energetic electrons energetic particles acceleration solar wind superhalo electrons

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KuaFu Mission

空间科学学报 2006年第Z1期26卷 25-29页

作者： XIA Lidong tu chuanyi Schwenn Rainer Donovan Eric Marsch Eckart WANG Jingsong ZHANG Yongwei XIAO Zuo 无 School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Department of Geophysics Peking University Max-Planck-Institut für Sonnensystemforschung Katlenburg-LindauGermany Department of Physics and Astronomy University of CalgaryCalgaryCanada National Center for Space Weather Monitoring and Warning China Meteorological Administration Dong Fang Hong Satelite Co.Ltd China Academny of Space Technology Center for Space Science and Applied Research Chinese Academry of Sciences

The KuaFu mission-Space Storms,Aurora and Space Weather Explorer-is an"L1+Polar"triple satellite project composed of three spacecraft:KuaFu-A will be located at L1 and have instruments to observe solar EUV and FUV emissions,and white-light Coronal Mass Ejections(CMEs),and to measure radio waves,the local plasma and magnetic field,and high-energy ***1 and KuaFu-B2 will bein polar orbits chosen to facilitate continuous 24 hours a day observation of the north polar Aurora *** KuaFu mission is designed to observe the complete chain of disturbances from the solar atmosphere to geospace,including solar flares,CMEs,interplanetary clouds,shock waves,and their geo-effects,such as magnetospheric sub-storms and magnetic storms,and auroral *** mission may start at the next solar maximum(launch in about 2012),and with an initial mission lifetime of two to three *** data will be used for the scientific study of space weather phenomena,and will be used for space weather monitoring and forecast *** overall mission design,instrument complement,and incorporation of recent technologies will target new fundamental science,advance our understanding of the physical processes underlying space weather,and raise the standard of end-to-end monitoring of the Sun-Earth system.

关键词： KuaFu Mission Space weather Solar-terrestrial relations

THE SPECTRAL INDEX AND THE RADIAL VARIATION OF THE STRONG ALFVNIC FLUCtuATIONS IN THE SOLAR WIND

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Chinese Science Bulletin 1988年第1期33卷 41-45页

作者：涂传诒 Department of Geophysics Peking University

Matthaeus and Goldstein pointed out that at high frequencies the spectral indexes of Alfv(?)nic fluctuations observed at 1 AU and 2.8 AU are very close to —5/3 (not—3/2). Burlaga, et al. showed that for increasing heliocentric distance, the frequency range with the spectral indexes around —5/3 is extending to low frequencies. To make an explanation for the observed results, a theoretical study is needed. What mechanism controls the properties of the Alfv(?)nic fluctuations in the solar

关键词： explanation SOLAR Goldstein quantities pointed haver extending fluctuation governing proton

The Yaglom Law and Cascade Rate in the Inner Heliosphere Observed by Helios 1 and 2

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The Yaglom Law and Cascade Rate in the Inner Heliosphere Obs...

GENERATION OF SUPRAHALO ELECTRONS BY MAGNETIC RECONNECTION IN THE SOLAR WIND SOURCE REGION

2022年中国地球科学联合学术年会

作者： Honghong Wu chuanyi tu Jiansen He Xin Wang Liping Yang Wuhan University Peking University Beihang University

The Yaglom law for the third-order structure functions of Els?sser fluctuations provides a route to estimate the energy cascade rate in the solar wind turbulence. However, not all solar wind is satisfied with the Yaglom law and the occurrence ratio is reported to be low in the high-latitude solar wind based on the Ulysses observations.

关键词：

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GENERATION OF SUPRAHALO ELECTRONS BY MAGNETIC RECONNECTION I...

A MODEL FOR THE VARIATIONS OF THE CRITICAL FREQUENCY OF F_2 LAYER DURING THE NEGATIVE PHASES OF IONOSPHERIC STORMS

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： Liping Yang Linghua Wang Jiansen He chuanyi tu ShzhangZhang Lei Zhang Xueshang Feng School of Earth and Space Sciences PekingUniversity SIGMA Weather Group State Key Laboratory for SpaceWeatherCenter for Space Science and Applied ResearchChineseAcademy of Sciences Institute of Geology and Geophysics ChineseAcademy of Sciences

Observations of solar wind electron population deviate considerably from aMaxwellian with enhanced numbers of suprathermal *** them,the origin of superhole electrons remains a *** this study,we investigatewhether superhalo electrons could be generated in the magnetic reconnectionmodel for solar wind origin suggested by tu et al.(2005a,b).To do this,a snapshot of the MHD simulation results as in our pervious work(Yang et al.2013)isused for a test particle simulation with the guiding center *** shows that electrons with an initially Maxwellian distribution at the temperature of about 105 K can be accelerated up to several hundred *** occurs mainly around the reconnection *** closer the electrons are the X-point,the higher the energy that the electrons earn is,which is aresult of the largest parallel component of the electric field at the *** trajectories are calculated to exhibit that the accelerated electrons primarilymove upwards along the open magnetic field,probably into the *** also examine the flux spectrum of-200 keV electrons,which displays asingle power law with an index of around *** many parameters,we findthat the power-law spectral index is most sensitive to the resistivity parameter *** alpha increases to 3,the spectral index becomes to about 1.3,which seemshard for superhole electrons.

关键词：

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Science China Mathematics 1983年第5期30卷 549-560页

作者：涂传诒贾志华 Department of Geophysics Peking University

A model for the negative phase of ionospheric storms in middle latitudes is presented. It is assumed that there will be molecule enriched air in the thermosphere above the auroral oval during the period of the main phase of a magnetic storm. The molecule enriched air is carried to the middle latitudes by thermospheric neutral wind, and at the same time it diffuses away. When the molecule enriched air arrives at the F2 layer above a station, the electron loss rate in the F2 layer increases, the electron density decreases and then the negative phase at the station begins. We have calculated the variations of the fo F2 following magnetic storms for Manzhouli （29.5°N, 117.5°E）, Freiburg （48°N, 07°E） and Billerica （43°N, 71°W） respectively. The results agree very well with typical events observed at the three stations and can be used to explain some average features of negative phase ionospheric storms in middle latitudes.

关键词： A MODEL FOR THE VARIATIONS OF THE CRITICAL FREQUENCY OF F2 LAYER DURING THE NEGATIVE PHASES OF IONOSPHERIC STORMS

INFLUENCE OF AURORAL ELECTRO JET ACTIVITY ON LOW-LATItuDE F-LAYER

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Chinese Science Bulletin 1985年第7期30卷 932-935页

作者：涂传诒张树理 Department of Geophysics Peking Unicersity

Ⅰ. INTRODUCTION turunen and Rao gave some examples to show a positive relation between the auroral disturbance and the anomalous decrease of f0F2 at an equatorial station Huancayo （12.0°S, 75.3°W）, and proposed that these anomalous decreases may be due to the enhancement of the fountain effect which causes the Appleton anomaly of the F-layer. As an extension of their work, Alamelu et al. studied the disturbed daytime behavior of f0F2 over the Indian zone on the same days

关键词： equatorial anomalous anomaly disturbance Indian latitude disturbed chosen marked storm

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纯基础研究的目的、经费来源和组织实施

科技导报 2019年第12期37卷 6-6页

作者：涂传诒北京大学地球与空间科学学院

1什么是纯基础研究纯基础研究的目的是开拓人类的知识,认识人类自己和长远物质自然环境,而不是当前的应用。纯基础研究的动力是兴趣。纯基础研究的成果是要在学术刊物上发表,或者在学术会议上报告,以促进学科发展。通常纯基础研究成果... 详细信息

1什么是纯基础研究纯基础研究的目的是开拓人类的知识,认识人类自己和长远物质自然环境,而不是当前的应用。纯基础研究的动力是兴趣。纯基础研究的成果是要在学术刊物上发表,或者在学术会议上报告,以促进学科发展。通常纯基础研究成果当时不能显现实际应用意义,在若干年之后,基础研究成果转化为应用技术时,它才有实际的意义。

关键词：基础研究组织经费自然环境学术刊物学术会议研究成果成果转化