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Science China(Technological Sciences) 2016年第7期59卷 1130-1136页

作者： LI ChenFang ZOU Hong ZONG QiuGang jia xianghong CHEN HongFei SHI WeiHong YU XiangQian Institute of Space Physics and Applied Technology School of Earth and Space Science Peking University State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center

The variation of the flux of energetic electrons in the magnetosphere has been proven to be strongly related to the solar wind speed. Observations of GEO orbit show that the flux of low-energy electrons is not only modulated by the solar wind speed, but, if a time delay is added, is also positively correlated to the flux of high-energy electrons. This feature provides a possible method to forecast the flux of high-energy electrons in GEO orbit. In this study, the correlations of the fluxes between the high-energy electrons and low-middle-energy electrons obtained at different L values and in different orbits are investigated to develop the application of this feature. Based on the analysis of long–term data observed by NOAA POES and GOES, the correlations between the fluxes of high-energy electrons and low–middle–energy electrons are good enough at different L values and in different orbits in quiet time, but this correlation is strongly affected by CME–driven geomagnetic storms.

关键词： magnetosphere high-energy electrons low-middle energy electrons forecast model

Radial propagation of magnetospheric substorm-injected energetic electrons observed using a BD-IES instrument and Van Allen Probes

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Science China Earth Sciences 2016年第7期59卷 1508-1516页

作者： ZONG QiuGang HAO YiXin ZOU Hong FU SuiYan ZHOU XuZhi REN Jie WANG LingHua YUAN ChongJing LIU ZhiYang jia xianghong QUAN Lin LIU Ying WANG YongFu Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China Institute of Geology and Geophysics Chinese Atcademy of SciencesBeijing 100029China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training CenterBeijing 100094China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094China

In cases where substorm injections can be observed simultaneously by multiple spacecraft,they can help elucidate the potential mechanisms of particle transport and energization,of great importance to understanding and modeling the *** this paper,using data returned from the BeiDa-IES（BD-IES） instrument onboard a satellite in an inclined（55°） geosynchronous orbit（IGSO）,in combination with two geo-transfer orbiting（GTO） satellite Van Allen Probes（A and B）,we analyze a substorm injection event that occurred on the 16 th of October *** this substorm injection,the IGSO onboard BD-IES was outbound,while both Van Allen Probe satellites（A and B） were inbound,a configuration of multiple trajectories that provides a unique opportunity to simultaneously investigate both the inward and outward radial propagation of substorm *** by AE/AL indices,this substorm was closely related to an IMF/solar wind discontinuity that showed a sharp change in IMF Bz direction to the *** innermost signature of this substorm injection was detected by Van Allen Probes A and B at L-3.7,while the outermost signature was observed by the onboard BD-IES instrument at *** data indicate that the substorm had a global,rather than just local,***,we suggest that electric fields carried by fast-mode compressional waves around the substorm injection are the most likely candidate mechanism for the electron injection signatures observed in the inner- and outermost inner magnetosphere.

关键词： Substonn injection Energetic electrons Energetic particle acceleration Drift Dispersionless injection

Monte Carlo simulations of the sensor head of imaging energetic electron spectrometer onboard a Chinese IGSO navigation satellite

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Science China(Technological Sciences) 2019年第7期62卷 1169-1181页

作者： ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei LUO Lin ZHOU XuZhi CHEN XingRan HAO YiXin REN Jie WANG YongFu SHI WeiHong YU XiangQian jia xianghong XU Feng ZHANG XiaoXin Institute of Space Physics and Applied Technology Peking University Beijing 100871 China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center Beijing 100094 China Key Laboratory of Space Weather National Center for Space Weather Beijing 100081 China

An imaging energetic electron spectrometer built by the Peking University team(BD-IES) onboard a Chinese navigation satellite in an inclined GEO orbit has been launched successfully in September 2015, which measures the spectra of the energetic electrons with the energy range of 50–600 keV in nine directions. In this study, Monte Carlo simulations of the BD-IES sensor head were performed using Geant4 and the corresponding characteristic responses to the isotropic energetic particles were derived. The effective geometric factors were estimated using the typical electron and proton spectra in the GEO orbit and the corresponding simulated sensor head responses. It was found that the average effective geometric factors of nine directions are close to the nominal geometric factors calculated with the traditional method, but the effective geometric factor decreases as the center energy of the energy channel decreases. The BD-IES sensor head also responses to the energetic protons, but the average contamination rate of all 72 channels is about 2%, which means that the proton contamination is acceptable. The spectra of the energetic electrons measured by BD-IES are derived using the effective geometric factors of the sensor head and are comparable with the spectra measured by the magnetic electron ion spectrometer(MagEIS) instrument onboard Van Allen Probes.

关键词： Monte Carlo simulation pin-hole imaging system geometric factor imaging energetic electron spectrometer IGSO satellite

Energetic electron detection packages on board Chinese navigation satellites in MEO

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Earth and Planetary Physics 2021年第2期5卷 158-179页

作者： YuGuang Ye Hong Zou Qiu-Gang Zong HongFei Chen JiQing Zou WeiHong Shi XiangQian Yu WeiYing Zhong YongFu Wang YiXin Hao ZhiYang Liu xianghong jia Bo Wang XiaoPing Yang XiaoYun Hao School of Earth and Space Sciences Peking UniversityBeijing 100871China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training CenterBeijing 100093China Shandong Aerospace Electro-technology Yantai Shandong 264000China

Energetic electron measurements and spacecraft charging are of great significance for theoretical research in space physics and space weather *** this paper,the energetic electron detection package(EEDP)deployed on three Chinese navigation satellites in medium Earth orbit(MEO)is *** instrument was developed by the space science payload team led by Peking *** EEDP includes a pinhole medium-energy electron spectrometer(MES),a high-energy electron detector(HED)based onΔE-E telescope technology,and a deep dielectric charging monitor(DDCM).The MES measures the energy spectra of 50−600 keV electrons from nine directions with a 180°×30°field of view(FOV).The HED measures the energy spectrum of 0.5−3.0 MeV electrons from one direction with a 30°cone-angle *** ground test and calibration results indicate that these three sensors exhibit excellent *** observations show that the electron spectra measured by the MES and HED are in good agreement with the results from the magnetic electron-ion spectrometer(MagEIS)of the Van Allen Probes spacecraft,with an average relative deviation of 27.3%for the energy *** charging currents and voltages measured by the DDCM during storms are consistent with the highenergy electron observations of the HED,demonstrating the effectiveness of the *** observations of the EEDP on board the three MEO satellites can provide important support for theoretical research on the radiation belts and the applications related to space weather.

关键词： radiation belts energetic electron detection Pin-hole technology Chinese navigation satellites MEO internal charging

Angular response of ‘pin-hole' imaging structure measured by collimated β source

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Science China(Technological Sciences) 2013年第12期56卷 2675-2680页

作者： ZOU Hong LUO Lin LI ChenFang jia xianghong XU Feng CHEN HongFei CHEN jiang SHI WeiHong YU XiangQian ZOU JiQing Institute of Space Physics and Applied Technology School of Earth and Space SciencePeking University State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center

The pitch-angle distribution of energetic particles is important for space physics studies on magnetic storm and particle acceleration.A‘pin-hole’imaging structure is built with the‘pin-hole’technique and a position sensitive detector,which can be used to measure the pitch angle distribution of energetic *** calibrate the angular response of the‘pin-hole’imaging structure,special experiment facilities are needed,such as the particle accelerator with special *** features of this kind of particle accelerator are:1)The energy range of the outgoing particles should be mid-energy particles(tens keV to several hundred keV);2)the particle flux should be consistent in time-scale;3)the directions of the outgoing particles should be the same and 4)the particle number within the spot should be low *** this paper,a method to calibrate the angular response of the‘pin-hole’imaging structure by the90Sr/90Y β source with a collimator is introduced and simulated by Geant4 *** result of the calibration with the collimated β source is in accord with the Geant4 simulations,which verifies the validity of this method.

关键词： 'pin-hole' imaging Energetic particle Pitch-angle distribution Angular response β source Geant4 simulation

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Imaging energetic electron spectrometer onboard a Chinese navigation satellite in the inclined GEO orbit

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Science China(Technological Sciences) 2018年第12期61卷 1845-1865页

作者： ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei ZOU JiQing CHEN jiang SHI WeiHong YU XiangQian ZHONG WeiYing WANG YongFu ZHOU XuZhi HAO YiXin CHEN XingRan jia xianghong XU Feng SHAO SiPei WANG Bo HAO XiaoYun ZHANG XiaoXin Institute of Space Physics and Applied Technology Peking University Beijing 100871 China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center Beijing 100094 China Shandong Aerospace Electro-technology Yantai 264000 China Key Laboratory of Space Weather National Center for Space Weather Beijing 100081 China

The energetic electron measurement is one of the most important issues to understand dynamics in space physics and the applications for space weather. In this study, the principle and functional components of the imaging energetic electron spectrometer(IES) onboard a Chinese navigation satellite in the inclined GEO orbit(IGSO) was introduced. The IES instrument is developed by the team in Peking University(BeiDa), thus it is named as BD-IES. Based on the pin-hole technique, the instrument can measure 50–600 keV electrons incident from 9 directions over a range of 180° in polar angle. With pulse height analysis(PHA), the spectrum can be determined for each direction. The energy and angular calibrations were performed, which show the good energy and angular characteristics of BD-IES. Monte Carlo simulations show that the anti-proton design of BDIES can effectively decrease the proton contamination on the electron measurements in the inclined GEO orbit. The primary results of BD-IES verify the successful design of this instrument.

关键词： imaging energetic electron spectrometer pin-hole imaging system IGSO satellite

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质子剂量微分谱预估空间辐射剂量

清华大学学报（自然科学版） 2006年第3期46卷 374-376页

作者：曾志李君利邱睿贾向红清华大学工程物理系北京100084 航天医学与工程研究所北京100094

利用M on te C arlo方法结合小体积元人体模型对航天员空间质子辐射剂量进行估算。使用核磁共振全身扫描图像,通过识别组织器官,再利用参考人数据,建立由4mm×4mm×4mm小体积元组成的人体模型。该人体模型包括23种辐射敏感器官,并用查... 详细信息

利用M on te C arlo方法结合小体积元人体模型对航天员空间质子辐射剂量进行估算。使用核磁共振全身扫描图像,通过识别组织器官,再利用参考人数据,建立由4mm×4mm×4mm小体积元组成的人体模型。该人体模型包括23种辐射敏感器官,并用查找表技术压缩模型数据。使用GEANT 4 M on te C arlo程序包,结合该模型,计算得到各个组织器官单能质子入射下的微分剂量估计谱库。对空间质子微分注量谱和微分剂量能谱积分,得到空间辐射剂量估计值。估算出1972年8月太阳质子事件的皮肤当量剂量为9 256 cSv,与文献值9 350 cSv相近,验证了算法的可行性。

关键词：空间辐射 Monte Carlo方法剂量预估体元模型

Estimation of Space Radiation Dose Using the Voxel Model from MRI

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Estimation of Space Radiation Dose Using the Voxel Model fro...

The Second Asian and Oceanic Congress for Radiation Protection

作者： jia xianghong Xu Feng Huang Zengxin (Astronaut Research and Training Center of China Beijing 100094 )

The space radiation environment consists of geomagnetically trapped proton and electrons, galactic cosmic radiation, and at times, high-energy solar particles that can penetrate spacecraft and spacesuits to produce a significant radiation exposure to crewmembers. In order to determine the astronaut radiation exposure and related health risks, the voxel male model has been developed and is used in conjunction with Monte Carlo particle transport and dose codes –GEANT4. We obtain organ absorbed doses and effective doses to the model in isotropic proton fields with energies ranging from 10MeV to 500MeV.

关键词： voxel human model MRI dose proton Monte Carlo GEANT4

来源： cnki会议评论

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纳秒脉冲空气辉光放电等离子体及应用

强激光与粒子束 2010年第10期22卷 2299-2302页

作者：万军贾向红宋铭炜王守国中国科学院微电子研究所微电子器件与集成技术重点实验室北京100029

采用基于半导体断路开关的纳秒脉冲高压电源,在两个金属电极之间产生放电区间为1 600mm×100 mm×25 mm的常压辉光空气等离子体。等离子体发生器采用负高压针电极阵列与平板阳极结构,针电极的直径为1 mm,长度为20 mm,针电极之间的间隔为... 详细信息

采用基于半导体断路开关的纳秒脉冲高压电源,在两个金属电极之间产生放电区间为1 600mm×100 mm×25 mm的常压辉光空气等离子体。等离子体发生器采用负高压针电极阵列与平板阳极结构,针电极的直径为1 mm,长度为20 mm,针电极之间的间隔为20 mm,针电极与平板零电位之间的距离为25mm,在每个负高压针电极末端周围同时形成圆锥形辉光放电,在平板地电极则形成大面积辉光放电。采用电压探针测量了该新型等离子体的放电特性,结果表明:放电脉冲的上升时间为26 ns,最高脉冲输出峰值电压为27 kV;利用该辉光等离子体对幅宽为1 000 mm聚四氟乙烯薄膜进行了表面改性处理,处理后其表面接触角由原来的124°降到69°,亲水性能大为提高。

关键词：纳秒脉冲放电半导体断路开关空气辉光等离子体表面处理

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用于空间辐射主动防护的等离子体发生器设计

真空科学与技术学报 2011年第4期31卷 481-484页

作者：贾向红许峰万军贾少霞王守国中国科学院微电子器件与集成技术重点实验室中国科学院微电子所北京100029 航天医学基础与应用国家重点实验室中国航天员科研训练中心北京100093

等离子引发磁膨胀技术被美国航空航天局推荐为最有工程应用价值的空间辐射主动防护技术。在该技术中,高密度等离子体发生器的设计是其中的关键技术之一。本文设计了一种高密度螺旋波等离子体发生器,采用13.56 MHz射频源激发等离子体天线... 详细信息

等离子引发磁膨胀技术被美国航空航天局推荐为最有工程应用价值的空间辐射主动防护技术。在该技术中,高密度等离子体发生器的设计是其中的关键技术之一。本文设计了一种高密度螺旋波等离子体发生器,采用13.56 MHz射频源激发等离子体天线,并将该等离子发生器偏心放置在表面磁感应强度为0.1 T的柱状永久磁铁内,以氩气为工作气体进行了真空舱磁膨胀实验。利用朗缪尔探针,对发生器产生的等离子体密度及温度随输入功率的变化进行了测量,该发生器成功地引发了磁铁磁场膨胀。

关键词：螺旋波空间辐射主动防护等离子体发生器