Mathematics – Logic
Scientific paper
May 2002
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002aas...200.2007w&link_type=abstract
American Astronomical Society, 200th AAS Meeting, #20.07; Bulletin of the American Astronomical Society, Vol. 34, p.674
Mathematics
Logic
Scientific paper
Coronal mass ejections (CMEs) have been called ``the most energetic events in the solar system." In one widely accepted scenario, the energy that drives mass ejections accumulates slowly in the corona over a period of some days before the eruptive outburst that marks the start of the mass ejection. That accumulated energy must be sufficient not only to accelerate the ejected mass and to lift it against solar gravity, but it must also open the coronal magnetic field to allow the plasma egress to interplanetary space. The well-known Aly-Sturrock theorem shows that it is impossible to store sufficient energy in a simple force-free magnetic arcade, since the upper bound for such force-free energy is that of the fully open field only. We have shown in earlier work that additional energy, sufficient to lift and accelerate the ejecta, can be obtained from non-force-free currents. This assumes that force-free currents are responsible for enough energy to open the field. However, the Aly-Sturrock theorem only sets an upper bound; it does not guarantee the existence simple force-free states whose energy approaches that bound. In the present work, we explore force-free equilibria of simple magnetic arcades, and show that it may not always be possible to store sufficient energy to open the field without topological changes such as the formation of current sheets or detached flux ropes. Just how much energy can be stored appears to depend on details of the magnetic flux distribution at the coronal base, and on the shear profile applied to the base field. Our results also suggest that force-free fields including detached flux ropes may exceed the Aly-Sturrock energy limit.
No associations
LandOfFree
Upper Bounds for Energy Storage in Coronal Magnetic Arcades 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 Upper Bounds for Energy Storage in Coronal Magnetic Arcades, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Upper Bounds for Energy Storage in Coronal Magnetic Arcades will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1717672