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Plasma Science and Technology 2024年第3期26卷 83-87页

作者：徐栩涛徐田超肖池阶张祖煜何任川袁瑞鑫许平 State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China School of Physics Xihua UniversityChengdu 610039People's Republic of China

The diagnostic of poloidal magnetic field(B_(p))in field-reversed configuration(FRC),promising for achieving efficient plasma confinement due to its highβ,is a huge challenge because B_(p)is small and reverses around the core *** laser-driven ion-beam trace probe(LITP)has been proven to diagnose the B_(p)profile in FRCs recently,whereas the existing iterative reconstruction approach cannot handle the measurement errors *** this work,the machine learning approach,a fast-growing and powerful technology in automation and control,is applied to B_(p)reconstruction in FRCs based on LITP principles and it has a better performance than the previous *** machine learning approach achieves a more accurate reconstruction of B_(p)profile when 20%detector errors are considered,15%B_(p)fluctuation is introduced and the size of the detector is remarkably ***,machine learning could be a powerful support for LITP diagnosis of the magnetic field in magnetic confinement fusion devices.

关键词： FRC LITP poloidal magnetic field diagnostics machine learning

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2A tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2A Team Southwestern Institute of Physics Chengdu 610041People's Republic of China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2A *** 20-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2026 mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82%at 122 nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~280 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2A campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

Inward particle transport driven by biased endplate in a cylindrical magnetized plasma

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Plasma Science and Technology 2024年第3期26卷 126-130页

作者：盖跃徐田超肖池阶郭志彬王晓钢何任川杨肖易张祖煜袁瑞鑫 State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China Department of Physics Harbin Institute of TechnologyHarbin 150001People's Republic of China

The inward particle transport is associated with the formation of peaked density profiles,which contributes to improve the fusion rate and the realization of steady-state *** active control of inward particle transport is considered as one of the most critical issues of magnetic confinement ***,it is realized preliminarily by adding a biased endplate in the Peking University Plasma Test(PPT)*** results reveal that the inward particle flux increases with the bias voltage of the *** is also found that the profile of radial electric field(Er)shear is flattened by the increased bias *** velocity fluctuations affect the inward particle more than density fluctuations,and the frequency of the dominant mode driving inward particle flux increases with the biased voltage applied to the *** experimental results in the PPT device provide a method to actively control the inward particle flux using a biased endplate and enrich the understanding of the relationship between E_(r)×B shear and turbulence transport.

关键词： inward particle transport biased endplate turbulent transport

Laboratory observation of electron energy distribution near three-dimensional magnetic nulls

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Plasma Science and Technology 2024年第3期26卷 46-52页

作者：何任川徐田超杨肖易肖池阶张祖煜袁瑞鑫王晓钢郭志彬余修铭盖跃 State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China Department of Physics Harbin Institute of TechnologyHarbin 150001People's Republic of China

The acceleration of electrons near three-dimensional(3D)magnetic nulls is crucial to the energy conversion mechanism in the 3D magnetic reconnection *** explore electron acceleration in a 3D magnetic null topology,we constructed a pair of 3D magnetic nulls in the PKU Plasma Test(PPT)device and observed acceleration of electrons near magnetic *** study measured the plasma floating potential and ion density profiles around the 3D magnetic *** potential wells near nulls may be related to the energy variations of electrons,so we measured the electron distribution functions(EDFs)at different spatial *** axial variation of EDF shows that the electrons deviate from the Maxwell distribution near magnetic *** scanning probes that can directionally measure and theoretically analyze based on curve fitting,the variations of EDFs are linked to the changes of plasma potential under 3D magnetic null *** kinetic energy of electrons accelerated by the electric field is 6 eV(v_(e)~7v_(Alfvén-e))and the scale of the region where accelerating electrons exist is in the order of serval electron skin depths.

关键词： electron acceleration EEDF 3D magnetic null magnetic reconnection

In-flight vector magnetometer calibration for FY-3E satellite

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Science China(Technological Sciences) 2023年第6期66卷 1867-1868页

作者： WANG YongFu YU XiangQian ZONG QiuGang xiao chijie LIU Si CHEN HongFei ZOU Hong SHI WeiHong School of Earth and Space Sciences Peking UniversityBeijing 100871China School of Physics Peking UniversityBeijing 100871China School of Physics and Electronic Science Changsha University of Science&TechnologyChangsha 410114China

The FY-3E meteorological satellite was launched by China on July 5,*** orbit of the satellite is sun-synchronous with an orbit altitude 836 km and orbit period 102 *** satellite is equipped with a triaxial anisotropic magnetore-sistance magnetometer to detect ultra-low frequency waves in the *** magnetometer sensor is situated on the satellite *** is approximately 1 m away from the satellite body to reduce the effect of spacecraft fields.

关键词： magnetometer satellite equipped

Practicable method to identify ferromagnetic objects

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Science China(Technological Sciences) 2022年第12期65卷 3079-3081页

作者： YU XiangQian WANG YongFu xiao chijie LIU Si ZONG QiuGang CHEN HongFei ZOU Hong SHI WeiHong CHEN Ao School of Earth and Space Sciences Peking UniversityBeijing 100871China School of Physics Peking UniversityBeijing 100871China School of Physics and Electronic Science Changsha University of Science&TechnologyChangsha 410114China

Ferromagnetic objects are ubiquitous in the world and the identification of ferromagnetic objects is important in many *** the position and magnetic parameters of the ferromagnetic object from its magnetic signature i... 详细信息

关键词： ferromagnetic signature mining

AC vector magnetometer for space-based applications using low-resource magneto-impedance sensor

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Science China(Technological Sciences) 2023年第12期66卷 3663-3670页

作者： YU XiangQian HUANG Cong xiao chijie LI JiaWei LIU Si WANG JingDong LI YunPeng QU YaNan WANG YongFu CHEN HongFei ZOU Hong SHI WeiHong ZONG QiuGang CHEN xiaoFei ZHANG xiaoXin ZONG WeiGuo WANG JingSong School of Earth and Space Sciences Peking UniversityBeijing 100871China Key Laboratory of Space Weather National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081China Innovation Center for Feng-Yun Meteorological Satellite(FYSIC) Beijing 100081China School of Physics Peking UniversityBeijing 100871China School of Physics and Electronic Science Changsha University of Science&TechnologyChangsha 410114China Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100190China Institute of Shandong Aerospace Technology Yantai 264003China Shanghai Institute of Satellite Engineering(SISE) Shanghai 201108China

This study proposes a novel AC vector magnetometer developed using a low-resource magneto-impedance sensor for China’s Feng-Yun meteorological satellite(FY-3E).It was calibrated and characterized to determine its performance *** total weight of the AC vector magnetometer is 51 g(the aluminum box excluded),while the total power consumption is 310 m *** proposed AC vector magnetometer can detect magnetic field variations in the range of±1000 nT and noise power spectral density of≤50 pT/Hz^(1/2)@1 ***,the proposed device has a maximum nonlinearity of≤0.71‰over the entire range and a nonorthogonality error of 3.07 nT or 0.15%(root mean square).The total dose hardness of the sensor is≥30 krad(Si).Furthermore,we propose the first survey results of a magnetometer equipped aboard a Chinese FY-3E satellite in a Sunsynchronous *** data revealed that the AC vector magnetometer can detect transient physical signals such as quasistatic field-aligned currents(~50 nT)and waves at the auroral *** features render the proposed AC vector magnetometer suitable for space-based applications,particularly those involving the study of geomagnetic activity.

关键词： AC vector magnetometer low-resource magneto-impedance sensor FY-3E satellite

Recent progresses in theoretical studies and satellite observations for collisionless magnetic reconnection

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Chinese Science Bulletin 2012年第12期57卷 1369-1374页

作者： WANG xiaoGang xiao chijie PU ZuYin WANG JiaQi School of Physics and State Key Laboratory of Nuclear Physics ＆ Technology Peking University Beijing 100871 China School of Earth and Space Sciences Peking University Beijing 100871 China College of Physical Science and Technology Sichuan University Chengdu 610064 China

As an essential mechanism in large scale fast magnetic energy releases and field reconfigurations processes in space,astrophysical, and laboratory plasmas,magnetic reconnection,particularly collisionless magnetic reconnection,has been studied for more than 65 *** progresses have been achieved in recent years and basic features of the process have been well understood,largely due to more and more satellite observation data available in the last ***,a few outstanding issues are still remained *** in the paper review the development of collisionless magnetic reconnection studies and major achievements in recent years,and also briefly discuss the open questions remained to be answered in studies of collisionless magnetic reconnection.

关键词：卫星观测数据磁场重联碰撞天体物理学配置过程空间领域能量释放等离子体

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子午工程二期宽频地磁波监测仪研制

地球与行星物理论评（中英文） 2024年第1期55卷 6-14页

作者：于向前和冬华肖池阶宗秋刚施伟红刘斯陈鸿飞王永福邹鸿北京大学地球与空间科学学院北京100871 北京大学物理学院北京100871 长沙理工大学物理与电子科学学院长沙410114

地球的磁层中存在各种波现象,其频率从mHz延伸到数千Hz.这些波的研究一直是空间物理学研究的核心问题.针对目前世界上地磁台站的波监测设备均为各自测量相对变化、缺乏统一标定、无法进行从高纬到低纬联合观测、无法进行多台设备观测数... 详细信息

地球的磁层中存在各种波现象,其频率从mHz延伸到数千Hz.这些波的研究一直是空间物理学研究的核心问题.针对目前世界上地磁台站的波监测设备均为各自测量相对变化、缺乏统一标定、无法进行从高纬到低纬联合观测、无法进行多台设备观测数据的统一对比研究的现状,本文综合使用磁阻传感器(探测ULF频段:1 mHz~2 Hz)、巨磁感抗传感器(探测ELF频段:0.2 Hz~2 kHz)和线圈传感器(探测VLF频段:0.2 kHz~10 kHz)研制新一代的宽频地磁波监测仪,将这些监测仪放置在120°E子午链附近的黑龙江漠河站(高纬)、北京十三陵站(中纬)、海南乐东站(低纬)等典型区域的地磁台站上,并对各个台站的设备进行统一的时间、振幅和频率标定,结合FY-3E、SMILE等近地空间卫星数据,全面提升对地球磁层的各种波现象的探测能力.研制的宽频地磁波监测仪的性能测试实验表明,其具有对一定频率(1 mHz~10 kHz)的波的探测能力;其幅度探测范围为:±65000 nT(ULF频段)、±1000 nT(ELF频段)、±100 pT(VLF频段);在量程范围内又具有较低的非线性误差:ULF频段≤0.0446%、ELF频段≤0.51%、VLF频段≤1.18%;噪声水平也较低:RMS(方均根)噪声≤0.5554 nT(ULF频段)、NPS(功率谱)噪声≤0.028 nT/√Hz(ELF频段)、NPS(功率谱)噪声≤0.24 pT/√Hz(VLF频段).所有这些特点使得所提出的宽频地磁波监测仪能够满足子午工程二期的波探测需求.

关键词：子午工程二期宽频地磁波监测仪磁阻传感器巨磁感抗传感器线圈传感器

Recent studies in satellite observations of three-dimensional magnetic reconnection

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Science China(Technological Sciences) 2007年第3期50卷 380-384页

作者： xiao chijie WANG xiaoGang PU ZuYin MA ZhiWei ZHAO Hui ZHOU GuiPing WANG JingXiu LIU ZhenXing National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China School of Physics Peking UniversityBeijing 100871China School of Earth and Space Sciences Peking UniversityBeijing 100871China Institute for Fusion Theory and Simulation Zhejiang UniversityHangzhou 310027China Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100080China

Magnetic reconnection is a main process converting the magnetic energy into thermal and kinetic energy in plasmas. It is one of the fundamental problems of crucial importance not only to space plasmas physics and space weather studies,such as the solar flare,coronal mass ejections and magnetospheric substorms,but also to the stability analysis in magnetically confined fusion. In general,except for cases with periodical boundary conditions,three-dimensional(3D) magnetic re-connection occurs on magnetic separatrices generated by magnetic nulls. Here we briefly introduce/review the theories and some recent satellite observations of 3D magnetic reconnection. Topics to be further studied are also discussed.

关键词： magnetic reconnection null separatrix separator X-point X-line