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arXiv · 0910.1188

Linking remote imagery of a coronal mass ejection to its in situ signatures at 1 AU

Christian Möstl·Charles J. Farrugia·Manuela Temmer·Christiane Miklenic·Astrid M. Veronig·Antoinette B. Galvin·Martin Leitner·Helfried K. Biernat
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Abstract

In a case study (June 6-7, 2008) we report on how the internal structure of a coronal mass ejection (CME) at 1 AU can be anticipated from remote observations of white-light images of the heliosphere. Favorable circumstances are the absence of fast equatorial solar wind streams and a low CME velocity which allow us to relate the imaging and in-situ data in a straightforward way. The STEREO-B spacecraft encountered typical signatures of a magnetic flux rope inside an interplanetary CME (ICME) whose axis was inclined at 45 degree to the solar equatorial plane. Various CME direction-finding techniques yield consistent results to within 15 degree. Further, remote images from STEREO-A show that (1) the CME is unambiguously connected to the ICME and can be tracked all the way to 1 AU, (2) the particular arc-like morphology of the CME points to an inclined axis, and (3) the three-part structure of the CME may be plausibly related to the in situ data. This is a first step in predicting both the direction of travel and the internal structure of CMEs from complete remote observations between the Sun and 1 AU, which is one of the main requirements for forecasting the geo-effectiveness of CMEs.

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Christian Möstl, Charles J. Farrugia, Manuela Temmer, Christiane Miklenic, Astrid M. Veronig, Antoinette B. Galvin, Martin Leitner, Helfried K. Biernat. 2009-10-07. Linking remote imagery of a coronal mass ejection to its in situ signatures at 1 AU. https://doi.org/10.1088/0004-637x%2F705%2F2%2Fl180

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