HR: 08:30h
AN: SH51C-03    [Abstracts]
TI: Multiple Flux Ropes and Helicity Bounds in a Force-Free Corona
AU: * Wolfson, R
EM: wolfson@middlebury.edu
AF: Department of Physics, Middlebury College, Middlebury, VT 05753, United States
AU: Pathak, K
EM: kanchanpathak@gmail.com
AF: Department of Physics, Middlebury College, Middlebury, VT 05753, United States
AB: Magnetic flux ropes are twisted, elongated bundles of magnetic flux that serve as repositories of magnetic energy in the solar corona. Flux ropes are prevalent over solar active regions and in the cavities that underlie coronal streamers. As such, they may provide at least some of the energy that powers a range of solar events, including flares, prominence eruptions, and coronal mass ejections. We have shown previously that energy storage in coronal flux ropes is enhanced when a potential magnetic field overlies a region of sheared fields that includes a flux rope. In the present work we demonstrate solutions for a force-free corona that include multiple flux ropes whose locations extend high into the solar atmosphere. We also derive an upper bound on the magnetic helicity associated with these multiple-rope solutions, and show that the actual helicity approaches closer to the upper bound as the shearing of magnetic footpoints is confined to ever-smaller regions at the coronal base. This work was supported by NASA grant NNG04GB91G to Middlebury College.
DE: 2134 Interplanetary magnetic fields
DE: 7509 Corona
DE: 7513 Coronal mass ejections (2101)
DE: 7524 Magnetic fields
DE: 7531 Prominence eruptions
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Fall Meeting