Prominences and flares

It is believed that prominences exist at potential-energy minima (i.e., in 'magnetic holes'). This paper describes observations demonstrating the role played by a preflare prominence (filament) in the occurrence of flares, analyzing a case of an evolving prominence in an active region at the time of the emergence of opposite-polarity magnetic flux. The counterpolar magnetic flux dissipates and heats up the filament and the area underneath; at some moment, the character of the energy loss is changed, disrupting the equilibrium and causing the appearance of a flare.