Astronomy and Astrophysics – Astrophysics
Scientific paper
May 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005agusmsh54b..01m&link_type=abstract
American Geophysical Union, Spring Meeting 2005, abstract #SH54B-01
Astronomy and Astrophysics
Astrophysics
7500 Solar Physics, Astrophysics, And Astronomy, 7513 Coronal Mass Ejections, 7519 Flares, 7524 Magnetic Fields, 7531 Prominence Eruptions
Scientific paper
From chromospheric and coronal images and line-of-sight and vector magnetograms of magnetic regions that produce CMEs, and from chromospheric and coronal movies of the onsets of CME eruptions, it appears that the magnetic field that explodes to drive the CME is initially the strongly sheared core of a magnetic arcade encasing a polarity dividing line in the magnetic flux. Before or during the onset of the explosion, the sheared core field becomes a flux rope, often carrying chromospheric material within it. For the erupting flux rope to drive the explosion, that is, for its magnetic energy content to decrease in the explosion, the flux rope's cross-sectional area must increase faster than its length. For instance, for isotropic expansion, the area increases as the square of the length, and the magnetic energy content of the flux rope decreases as the inverse of the length. The instability that initiates the eruption of the flux rope might be an ideal MHD kink instability, or might involve runaway tether-cutting reconnection. The reconnection begins below the flux rope (internal to the arcade) when the overall field configuration of the region is effectively that of a single bipole. When the flux rope resides in a multi-bipolar configuration having a magnetic null above the flux rope, the runaway tether-cutting reconnection might begin either below the flux rope or at the null above (external to) the arcade. We present examples of observed CME onsets that illustrate the above alternatives. In each example, reconnection below the flux rope begins early in the eruption. This indicates that internal tether cutting reconnection (classic tether-cutting reconnection) is important in unleashing the CME explosion in all cases, including those in which the explosion may be triggered by MHD kinking or by external reconnection (classic breakout reconnection).
Falconer David Allen
Gary Gilmer A.
Moore Robert L.
Sterling Alphonse C.
No associations
LandOfFree
Shape and Reconnection of the Exploding Magnetic Field in the Onset of CMEs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Shape and Reconnection of the Exploding Magnetic Field in the Onset of CMEs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Shape and Reconnection of the Exploding Magnetic Field in the Onset of CMEs will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1694899