MAGNETIC MERGING IN COLLIDING FLUX TUBES

We develop an analytical theory of reconnection between colliding, twi sted magnetic flux tubes. Our analysis is restricted to direct collisi ons between parallel tubes and is based on the collision dynamics work ed out by Bogdan (1984). We show that there is a range of collision ve locities for which neutral point reconnection of the Parker-Sweet type can occur, and a smaller range for which reconnection leads to coales cence. Mean velocities within the solar convection zone are probably s ignificantly greater than the upper limit for coalescence. This sugges ts that the majority of flux tube collisions do not result in merging, unless the frictional coupling of the tubes to the background flow is extremely strong.