Previous abstract Next abstract
Session 86 - Coronal Activity.
Oral session, Thursday, June 13
The effects of shear-driven magnetic reconnection in a 2.5D quadrupolar magnetic topology have been calculated previously (Karpen, Antiochos amp; DeVore 1995, ApJL, 460, L73). A quadrupolar topology in the solar corona corresponds to the interaction of two sheared closed magnetic arcades of opposite polarity. The key result of the previous work is that the reconnection proceeds by the creation of a long current sheet and the sporadic formation of magnetic islands along that sheet. This leads to the creation of numerous current sheets over a large volume of the post-reconnection field. Magnetic reconnection has also been frequently proposed, however, as the origin of the heating and acceleration in coronal hole regions. The relevant topology in this case must be that of a closed magnetic arcade and an open flux system. In addition, reconnection of open field should be more appropriate for phenomena such as eruptive flares and coronal mass ejections. Consequently, we have simulated numerically the interaction of a closed bipolar arcade and an open field flux system. A major difference between this simulation and the previous case is that the boundary conditions at the top of the simulation box can play an important role in the evolution of the reconnection region. We present the results of our simulations, and contrast them the results for the quadrupole case. In addition, we discuss the physical reason for the creation of long current sheets during the reconnection process.
Program listing for Thursday