Quasi-static evolution in multiple arcades

The slow dynamical evolution of solar atmospheric magnetic field structures via the equilibrium equation has been the subject of a number of investigations. In many of these studies the quasi-static evolution of the field and the associated plasma has been investigated for a single arcade structure. In this paper we present results for multiple arcade structures. For multiple arcades we do not find bifurcations and the consequent multiple solutions as the field is evolved through a sequence of equilibrium states, in contrast to the findings for single arcade. Further we show that particular polarity arrangements within a pair of arcade structures lead to quite different topologies of the field as it is evolved. When new flux emerges from the photospheric boundary under a pre-existing magnetic arcade the results suggest that such a mechanism will initiate coronal mass ejection.