共查询到16条相似文献,搜索用时 578 毫秒
1.
中性原子成像仪(NAIS-H)获取的高时空分辨率图像可为地球空间磁暴和亚暴过程的各类机制研究提供全景式的空间粒子分布数据,为磁层与电离层耦合、磁层能量耗散等MIT(磁层elax-elax电离层elax-elax热层耦合小卫星星座探测计划)科学研究任务提供重要的数据支撑.探测器的标定是研制过程的一个重要技术环节,是日后空间探测数据分析和反演基本依据.本文利用模拟信号源对中性原子成像仪原理样机的前端电子学系统进行了能谱定标,并利用电子加速器对标定的能谱进行了辐射测试验证. 相似文献
2.
3.
正英国空间局(UKSA)网站2017年10月30日报道,UKSA将为太阳风-磁层相互作用全景成像卫星(SMILE)任务提供300万英镑的资助,用于开发SMILE的软X射线成像仪(SXI)。SMILE任务计划于2021年发射,将首次实现对地球磁层的整体成像观测,揭示磁层大尺度结构及其对太阳风扰动的响应,增进对日地关系的认识。UKSA此次资助将支持3个英国学术团队开展 相似文献
4.
采用已经建立的环电流离子解析模型,结合Chamberlain地冕中性层模型,研究了2004年11月一次大磁暴期间的环电流区域中性原子(ENA)图像.结果表明,模拟的ENA图像与TC-2卫星搭载的中性原子成像仪(NUAUD)的观测图像在方位角或地方时分布、高度或纬度分布和能谱分布方面存在一定的差异.如果依据磁暴发展的不同阶段来选择环电流离子模型的方位角不对称因子和通量最大方向的方位角,增大地冕中性层在低高度区域的密度或者考虑氢(H)以外的其他中性成分,改进注入边界处的离子能谱分布函数,且考虑不同种类环电流离子的比例随磁暴发展可能发生的变化,该模型有望产生更符合观测的模拟ENA图像. 相似文献
5.
6.
7.
2003年12月30日发射的中国探测-1卫星是"地球空间双星探测计划"(简称"双星计划")中的第1颗卫星,运行在赤道轨道.2004年7月25日,"双星计划"的第2颗卫星--探测-2由长征-2C改进型火箭送入地球极轨道.这2颗探测地球磁层空间的卫星分别运行于目前国际上地球空间探测卫星尚未覆盖的重要活动区,主要用于研究太阳活动、行星际磁层空间暴和灾害性地球空间天气的物理过程. 相似文献
8.
针对空间天气活动机理、机制及规律等方面研究需要,Kuafu卫星计划提出对日冕中性原子进行成像观测.通过分析日冕中性原子观测的科学意义和观测方法,采用编码调制方法进行日冕中性原子成像,并依据科学指标完成了整个仪器初步方案设计和仿真计算.仪器测量的中性原子能量范围为0.5~6MeV,视场范围为360°×10°.利用高压静电偏转电极板去除测量范围内的带电粒子,仪器由m序列编码调制栅网与硅半导体构成的成像结构及电子学箱共同组成.编码成像方案和仿真计算奠定了日冕中性原子成像观测的技术基础,可为空间天气中长期规律及预报等研究提供技术手段. 相似文献
9.
10.
11.
M.G. Henderson G.D. Reeves A.M. Jorgensen H.E. Spence L.A. Frank J.B. Sigwarth J.F. Fennell J.L. Roeder J.B. Blake K. Yumoto S. Bourdarie 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2000,25(12):2407-2416
The CEPPAD Imaging Proton Spectrometer on the POLAR spacecraft has proven to perform very well as an Energetic Neutral (ENA) atom imager, despite the fact that it was designed primarily for measuring energetic ions in-situ. ENAs emitted from the ring current can be detected during storm- as well as quiet-time conditions and can be monitored continuously for many hours at a time when Polar is situated in the polar cap. In addition, we are able to routinely detect ‘bursts’ of ENA emissions in response to substorm-associated ion injections. In this paper, we present ENA images of a single such event together with global auroral imager data from the POLAR VIS instrument. LANL geosynchronous energetic particle data, and ground magnetic Pi2 data in order to establish that such bursts are indeed caused by substorm injections. 相似文献
12.
13.
能量中性原子(Energetic Neutral Atoms, ENA, 简称能原子)是指在日球层内外空间, 拥有>0.1keV动能的原子.在此空间领域并没有温度>106K的中性气体, 但却充满动能>0.1keV的正离子.因此能原子A应该是A+离子与原地稀薄气体B原子或分子交换电荷所产生的, 即A++B→A+B+. 电荷交换涉及极小的动能变化, 新生的能原子A和离子B+基本上各自保持原有动能. 离子B+随即被当地磁场俘获, 能原子A则脱离磁场约束并携带其原属离子群的成分和能量信息而直线运动, 成为遥测空间等离子体的有效媒介. 美国人造卫星 IBEX (Interstellar Boundary Explorer) 直接探测得到来自日球层以外星际空间的能原子, 大幅延伸了利用能原子遥测空间等离子体的领域. 本文据此论述了空间能原子的发现, 综述了探测空间能原子的基本概念与实例、取得的主要成果、仪器设计和研制进展以及未来空间利用能原子遥测的发展趋势. 相似文献
14.
Edmond C. Roelof 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1989,9(12):195-203
Energetic neutral atom (ENA) images of the storm-time ring current obtained from the ISEE-1 spacecraft provide information for a “zero-order” global model of the energetic ion distribution. With the assumption of isotropic pressure and magnetostatic, non-convective pressure balance, the global system of electrical currents driven by the ion pressure can be calculated using Euler potentials for the divergenceless current density. Radial pressure gradients drive azimuthal currents, and azimuthal pressure gradients drive radial currents. The radial currents cause current lines in the inner magnetosphere to close in the ionosphere, forming a “partial” ring current. The intensities and locations of these field-aligned currents driven into and out of the ionosphere resemble those of the observed Region 2 current system, but not all observed properties of the Region 2 system are reproduced by the “zero-order” model. 相似文献
15.
James F. Carbary Stamatios M. KrimigisDonald G. Mitchell C. ParanicasP. Brandt 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The Magnetospheric Imaging Instrument (MIMI) on the Cassini spacecraft has observed energetic neutral atoms (ENA) and charged particles at Saturn from mid-2004 to the present. The particles often but not always reveal striking periodic behavior that seems to depend on the type of particle and spacecraft location. When subjected to a Lomb periodogram analysis, energetic electrons (>150 keV) exhibited strong frequency peaks near 10.80 h (the nominal or “base” period of Saturn kilometric radiation) during 2006–2008, but essentially no periodicity during 2005. The electron periodograms also show pronounced “double” frequency peaks in 2007 and 2008. Energetic protons (3–26 keV) show strong peaks near the same period for 2005–2007, but none for 2008. Oxygen ions at the same energies display strong peaks for 2005 and 2006, but not for 2007 and 2008. By projecting the ENA images onto Saturn’s equatorial plane or onto a plane perpendicular to the equatorial plane and then summing the data in the appropriate dimension, “strip” images can be constructed from which a time history can be derived. These time histories of ENA emissions are also subjected to a Lomb periodogram analyses. The energetic hydrogen neutrals (20–50 keV) exhibited periodic behavior only during 2007, while energetic oxygen neutrals (64–144 keV) displayed a strong SKR-like period in 2005 and 2006 but not for 2007 or 2008. Some of this behavior may be due to changing spacecraft aspect relative to the ENA emissions, and some of it may be real. This periodic behavior may be consistent with a rotating anomaly that “flashes” brightly in the midnight-to-dawn sector once per 10.8 h, with the flash parameters depending on particle species and energy. 相似文献
16.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1999,23(11):1837-1840
We review the current status of the development of Gamma-Ray Spectrometer (GRS) for the Lunar mission SELENE. The GRS instrument will measure gamma-rays in the energy range from 100 keV to 9 MeV. The instrument is a high-purity Ge detector surrounded by BGO and plastic scintillators which are operated as an anticoincidence shield, and is cooled by a Stirling cycle cryocooler. The primary objective is to provide global maps of the lunar composition. Measurements are anticipated for Fe, Ti, U, Th, K, Si, Mg, Al, O, Ca and Na over the entire lunar surface. The abundance of water ice in the permanently shaded craters at both the lunar poles will be measured with this instrument. 相似文献