Prospective White-light Imaging and In Situ Measurements of Quiescent Large-scale Solar-wind Streams from the Parker Solar Probe and Solar Orbiter
Prospective White-light Imaging and In Situ Measurements of Quiescent Large-scale Solar-wind Streams from the Parker Solar Probe and Solar Orbiter
复制标题
帕克太阳探测器和太阳轨道飞行器对静态大规模太阳风流的前瞻性白光成像和原位测量
DOI：
10.3847/1538-4357/aae978
复制
发表时间：
2018
影响因子：
4.9
通讯作者：
Zhou Yufen
中科院分区：
文献类型：
--
作者：
Xiong Ming;Davies Jackie A.;Feng Xueshang;Li Bo;Yang Liping;Xia Lidong;Harrison Richard A.;Hayashi Keiji;Li Huichao;Zhou Yufen
随着最近和即将分别发射的帕克太阳探测器（PSP）和太阳轨道器（SolO）任务，对内日球层的深空探索正处于前所未有的黄金时代。为了预测和理解PSP和SolO的未来观测结果，我们对太阳极小期的三维内日球层进行了正演MHD模拟，并合成了日冕和日球层等离子体对太阳光汤姆森散射所产生的白光（WL）发射。在利用PSP和SolO WL观测资料重建静态大尺度太阳风流时，应同时考虑太阳自转和航天器轨道。当PSP的椭圆轨道由静止坐标系转换为旋转坐标系时，它就变成了多圈螺旋轨道。这个旋转的PSP轨道的最内层螺旋绕成一个封闭的“心形”形状，位于距离太阳80 R⊙左右。当PSP沿着这个“心形”轨迹行进时，它可以两次穿越一个旋转相互作用区域（CIR）。这样就可以在日冕和日球层进行相同CIR的原位测量。当PSP接近近日点时，日冕的WL辐射增加。偏振可以用来定位日冕中的主WL散射区域。利用SolO的黄道外视角的额外WL图像，可以在纵向维度上进一步解析PSP周围的大型结构。PSP和SolO之间的协调观测在区分背景CIRs和瞬态抛射物方面非常有希望。
Deep-space exploration of the inner heliosphere is in an unprecedented golden age, with the recent and forthcoming launches of the Parker Solar Probe (PSP) and Solar Orbiter (SolO) missions, respectively. In order to both predict and understand the prospective observations by PSP and SolO, we perform forward MHD modeling of the 3D inner heliosphere at solar minimum, and synthesize the white-light (WL) emission that would result from Thomson scattering of sunlight from the coronal and heliospheric plasmas. Both solar rotation and spacecraft trajectory should be considered when reconstructing quiescent large-scale solar-wind streams from PSP and SolO WL observations. When transformed from a static coordinate system into a corotating one, the elliptical orbit of PSP becomes a multiwinding spiral. The innermost spiral winding of this corotating PSP orbit takes the form of a closed “heart shape” within around 80 R⊙ of the Sun. PSP, when traveling along this “heart-shaped” trajectory, can cross a single corotating interaction region (CIR) twice. This enables in situ measurements of the same CIR to be made in both the corona and heliosphere. As PSP approaches perihelion, the WL radiance from the corona increases. Polarization can be used to localize the main WL scattering region in the corona. Large-scale structures around PSP can be further resolved in the longitudinal dimension, using additional WL imagery from the out-of-ecliptic perspective of SolO. Coordinated observations between PSP and SolO are very promising in the quest to differentiate background CIRs from transient ejecta.