Abstract:
An ongoing debate is how magnetic energy is released in solar flares, which type of
magnetic instabilities are responsible for triggering the energy release, and which magnetic topologies
are most likely to host the instabilities. In this connection magnetic reconnection has been a general
ingredient, with most of the previous work focussing on 2D reconnection. A natural extension to
this is to investigate reconnection in 3D topologies, in particular the behaviour of magnetic nulls
and the magnetic topology associated with them. This paper investigates the difference in dynamical
behaviour of a numerical domain that either contains a double null-point pair connected by a separator
or only a fraction of the separator defined by the null-points. The experiments show that nulls can
either accumulate current individually, or act together to produce a singular current collapse along
the separator. The implication of these results for the interpretation of coronal data is discussed.
