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

http://arxiv.org/abs/1508.01532


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.

Read this paper on arXiv…

S. Tiwari, D. Falconer, R. Moore, et. al.
Mon, 10 Aug 15
23/30

Comments: 8 pages, 3 figures, to appear in GRL