Sympathetic solar eruptions in quadrupolar magnetic configurations

Abstract:

Observations by SDO/AIA have renewed the interest in sympathetic solar
eruptions, i.e., of eruptions that occur simultaneously (or in short
succession) at different source regions in the corona. Recently, Torok
et al. (2011) developed an idealized numerical model for the trigger
mechanisms of sympathetic eruptions in so-called pseudo-streamers, which
consist of a tri-polar magnetic configuration with a parasitic polarity
in their center. Here we extend the work by Torok et al. by investigating
sympathetic eruptions in (the topologically somewhat more complex)
quadrupolar configurations, using MHD simulations.

We consider both symmetric and asymmetric initial configurations that
contain two or three flux ropes within the quadrupole. We find, different
to Torok et al. (2011), that magnetic reconnection induced by a first
eruption cannot just trigger, but also prevent subsequent eruptions.
In addition, a (relatively modest) asymmetry of the configuration may
fully suppress the occurrence of successive full eruptions, i.e., of
coronal mass ejections. We discuss the implications of these results
for our understanding of sympathetic eruptions.