Quasi Separator Reconnection
Priest and Demolin 1995 (GJR) suggested that reconnection can occur at space
locations where the magnetic field is non-zero and the field line mapping
between two foot points changes especially rapid. Kinematic investigations of
the changes in field line locations indicates that transport of field lines
close to these quasi separator surfaces require field line velocities above the
Alfven velocity to maintain the field line topology. This is not possible and
they suggest that magnetic reconnection is the solution to resolve this problem.
Numerical experiments of the suggested scenario have shown that this is in fact
not occurring. In a dynamical situation the magnetic field may change and
as a result the field lines experiences a stretching that builds up currents.
Where the current sheet reaches the numerical resolution a slow reconnection
will take place, but this is due to the shearing of the initial magnetic field
structure and not because of the fast change in the field line mapping. It is in
fact found that for this reconnection to take place a stagnation flow around the
current sheet region is required - just as it was found for the flux braiding experiments. The experiments therefore strongly
suggest that there is no difference between the two scenarios, in that they
both require fast changes in the field line mapping across the current sheet and
a stagnation type flow to compress the tangential changing magnetic field
components.
Papers
- Dynamical Investigation of 3D Reconnection in Quasi-Separatrix Layers in a Boundary-Driven Magnetic Field, JGR, 105, 5119, 2000.
Last updated 12.06.00