2015/10/21 by Rui Wang, Wang, Rui, Ying D. Liu +9 · 1 citation
Physics and Astronomy · #FOS: Physical sciences #Solar and Stellar Astrophysics (astro-ph.SR) #astro-ph.SR
paper · pdf · doi:10.48550/arxiv.1510.06177
21 pages, 7 figures, APJ
arxiv created 2015/10/21 · arxiv updated 2015/10/22
We study the role of the coronal magnetic field configuration of an active region in determining the propagation direction of a coronal mass ejection (CME). The CME occurred in the active region 11944 (S09W01) near the disk center on 2014 January 7 and was associated with an X1.2 flare. A new CME reconstruction procedure based on a polarimetric technique is adopted, which shows that the CME changed its propagation direction by around 28^∘ in latitude within 2.5 R_\odot and 43^∘ in longitude within 6.5 R_\odot with respect to the CME source region. This significant non-radial motion is consistent with the finding of Mostl et al. (2015). We use nonlinear force-free field (NLFFF) and potential field source surface (PFSS) extrapolation methods to determine the configurations of the coronal magnetic field. We also calculate the magnetic energy density distributions at different heights based on the extrapolations. Our results show that the active region coronal magnetic field has a strong influence on the CME propagation direction. This is consistent with the "channelling" by the active region coronal magnetic field itself, rather than deflection by nearby structures. These results indicate that the active region coronal magnetic field configuration has to be taken into account in order to determine CME propagation direction correctly.