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arXiv · 1110.0300

Constraining the Kinematics of Coronal Mass Ejections in the Inner Heliosphere with In-Situ Signatures

T. Rollett·C. Möstl·M. Temmer·A. M. Veronig·C. J. Farrugia·H. K. Biernat
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Abstract

We present a new approach to combine remote observations and in situ data by STEREO/HI and Wind, respectively, to derive the kinematics and propagation directions of interplanetary coronal mass ejections (ICMEs). We used two methods, Fixed-Phi and Harmonic Mean, to convert ICME elongations into distance, and constrained the ICME direction such that the ICME distance-time and velocity-time profiles are most consistent with in situ measurements of the arrival time and velocity. The derived velocity-time functions from the Sun to 1 AU for the three events under study (1-6 June 2008, 13-18 February 2009, 3-5 April 2010) do not show strong differences for the two extreme geometrical assumptions of a wide ICME with a circular front (Harmonic Mean) or an ICME of small spatial extent in the ecliptic (Fixed-Phi). Due to the geometrical assumptions, Harmonic Mean delivers the propagation direction further away from the observing spacecraft with a mean difference of ~25 degree.

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T. Rollett, C. Möstl, M. Temmer, A. M. Veronig, C. J. Farrugia, H. K. Biernat. 2012-02-06. Constraining the Kinematics of Coronal Mass Ejections in the Inner Heliosphere with In-Situ Signatures. https://doi.org/10.1007/s11207-011-9897-0

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