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arXiv · 1508.01532

Near-Sun Speed of CMEs and the Magnetic Non-potentiality of their Source Active Regions

Sanjiv K. Tiwari·David A. Falconer·Ronald L. Moore·P. Venkatakrishnan·Amy R. Winebarger·Igor G. Khazanov
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Abstract

We show that the speed of the fastest coronal mass ejections (CMEs) that an active region (AR) can produce can be predicted from a vector magnetogram of the AR. This is shown by logarithmic plots of CME speed (from the SOHO LASCO CME catalog) versus each of ten AR-integrated magnetic parameters (AR magnetic flux, three different AR magnetic-twist parameters, and six AR free-magnetic-energy proxies) measured from the vertical and horizontal field components of vector magnetograms (from the {\it Solar Dynamics Observatory's Helioseismic and Magnetic Imager}) of the source ARs of 189 CMEs. These plots show: (1) the speed of the fastest CMEs that an AR can produce increases with each of these whole-AR magnetic parameters, and (2) that one of the AR magnetic-twist parameters and the corresponding free-magnetic-energy proxy each determine the CME-speed upper-limit line somewhat better than any of the other eight whole-AR magnetic parameters.

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Sanjiv K. Tiwari, David A. Falconer, Ronald L. Moore, P. Venkatakrishnan, Amy R. Winebarger, Igor G. Khazanov. 2015-08-06. Near-Sun Speed of CMEs and the Magnetic Non-potentiality of their Source Active Regions. https://doi.org/10.1002/2015gl064865

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