USING COORDINATED OBSERVATIONS IN POLARIZED WHITE LIGHT AND FARADAY ROTATION TO PROBE THE SPATIAL POSITION AND MAGNETIC FIELD OF AN INTERPLANETARY SHEATH
USING COORDINATED OBSERVATIONS IN POLARIZED WHITE LIGHT AND FARADAY ROTATION TO PROBE THE SPATIAL POSITION AND MAGNETIC FIELD OF AN INTERPLANETARY SHEATH
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利用偏振白光和法拉第旋转的协调观测来探测行星际鞘的空间位置和磁场
DOI：
10.1088/0004-637x/777/1/32
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发表时间：
2013-08
影响因子：
4.9
通讯作者：
Ying D. Liu
中科院分区：
文献类型：
--
作者：
Ming Xiong;Jackie A. Davies;Xueshang Feng;Mathew J. Owens;Richard A. Harrison;Chris J. Davis;Ying D. Liu
日冕物质抛射（CME）可以通过可见光和无线电波段的直接成像连续跟踪内日球层的大部分。太阳风瞬变的白色光（WL）特征，例如CME，由自由电子对太阳光的汤姆逊散射产生，因此取决于观察几何形状和电子密度。来自河外星系和类星体的无线电波的法拉第旋转（FR），由于这种太阳风特征的存在而产生，取决于视线磁场分量B和电子密度。要了解协调WL和FR观测CME，我们执行前向磁流体动力学模型的地球导向的冲击和合成的签名，将遥感在一些广泛分布的Vantage位置在内日光层。除去背景太阳风的贡献，可以发现激波对WL和FR的增强。汤姆逊散射的效率取决于散射角，WL辐射率I大致按照表达式I <$r−3随日心距离r而减小。从L4和L5拉格朗日点可以很好地观察到地向激波下游的鞘区，证明了这些点在空间天气预报方面的好处。的主要散射网站rsheath和在该位置Msheath的等离子体的质量的空间位置可以推断出从冲击波相关的WL辐射增强的偏振。根据FR测量，然后可以估计rsheath处的局部B鞘。偏振WL和FR的同时观测不仅可以用来探测CME，而且可以诊断它们的等离子体和磁场性质。
Coronal mass ejections (CMEs) can be continuously tracked through a large portion of the inner heliosphere by direct imaging in visible and radio wavebands. White light (WL) signatures of solar wind transients, such as CMEs, result from Thomson scattering of sunlight by free electrons and therefore depend on both viewing geometry and electron density. The Faraday rotation (FR) of radio waves from extragalactic pulsars and quasars, which arises due to the presence of such solar wind features, depends on the line-of-sight magnetic field component B∥ and the electron density. To understand coordinated WL and FR observations of CMEs, we perform forward magnetohydrodynamic modeling of an Earth-directed shock and synthesize the signatures that would be remotely sensed at a number of widely distributed vantage points in the inner heliosphere. Removal of the background solar wind contribution reveals the shock-associated enhancements in WL and FR. While the efficiency of Thomson scattering depends on scattering angle, WL radiance I decreases with heliocentric distance r roughly according to the expression I∝r−3. The sheath region downstream of the Earth-directed shock is well viewed from the L4 and L5 Lagrangian points, demonstrating the benefits of these points in terms of space weather forecasting. The spatial position of the main scattering site rsheath and the mass of plasma at that position Msheath can be inferred from the polarization of the shock-associated enhancement in WL radiance. From the FR measurements, the local B∥sheath at rsheath can then be estimated. Simultaneous observations in polarized WL and FR can not only be used to detect CMEs, but also to diagnose their plasma and magnetic field properties.
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影响因子：
56.9
作者：
G. Levy;T. Sato;B. Seidel;C. Stelzried;J. Ohlson;W. Rusch
通讯作者：
G. Levy;T. Sato;B. Seidel;C. Stelzried;J. Ohlson;W. Rusch
影响因子：
--
作者：
Yuming Wang;P. Ye;Shui Wang
通讯作者：
Yuming Wang;P. Ye;Shui Wang
传播和相互作用过程中日冕物质抛射的加速和减速
影响因子：
--
作者：
Fang Shen;S. T. Wu;Xueshang Feng;Chin-Chun Wu
通讯作者：
Chin-Chun Wu
影响因子：
2.6
作者：
N. Szajko;G. Cristiani;C. Mandrini;A. Lago
通讯作者：
N. Szajko;G. Cristiani;C. Mandrini;A. Lago
DOI：
10.1051/0004-6361/201220535
发表时间：
2012-11
期刊：
arXiv: Solar and Stellar Astrophysics
影响因子：
--
作者：
P. Démoulin;S. Dasso;M. Janvier
通讯作者：
P. Démoulin;S. Dasso;M. Janvier