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arXiv · 2005.01238

Reconstructing solar wind inhomogeneous structures from stereoscopic observations in white-light: Solar wind transients in 3D

Abstract

White-light images from Heliospheric Imager-1 (HI1) onboard the Solar Terrestrial Relations Observatory (STEREO) provide 2-dimensional (2D) global views of solar wind transients traveling in the inner heliosphere from two perspectives. How to retrieve the hidden three-dimensional (3D) features of the transients from these 2D images is intriguing but challenging. In our previous work (Li et al., 2018), a 'correlation-aided' method is developed to recognize the solar wind transients propagating along the Sun-Earth line based on simultaneous HI1 images from two STEREO spacecraft. Here the method is extended from the Sun-Earth line to the whole 3D space to reconstruct the solar wind transients in the common field of view of STEREO HI1 cameras. We demonstrate the capability of the method by showing the 3D shapes and propagation directions of a coronal mass ejection (CME) and three small-scale blobs during 3-4 April 2010. Comparing with some forward modeling methods, we found our method reliable in terms of the position, angular width and propagation direction. Based on our 3D reconstruction result, an angular distorted, nearly North-South oriented CME on 3 April 2010 is revealed, manifesting the complexity of a CME's 3D structure.

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Xiaolei Li, Yuming Wang, Rui Liu, Chenglong Shen, Quanhao Zhang, Shaoyu Lyu, Bin Zhuang, Fang Shen, Jiajia Liu, Yutian Chi. 2020-05-04. Reconstructing solar wind inhomogeneous structures from stereoscopic observations in white-light: Solar wind transients in 3D. https://doi.org/10.1029/2019ja027513

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