RECURRING MINIFILAMENT ERUPTIONS PRODUCED BY A MAGNETIC BIPOLE ROTATION AND FLUX CANCELLATION

LÓPEZ FUENTES, M.C.; MANDRINI, C.H.; POISSON, M.; MAC CORMACK, C.; CRISTIANI, G.D.

Reunión virtual

Congreso; Committee on Space Research General Assembly; 2021

COSPAR

A series of confined plasma ejections produced by minifilament eruptions were observed in activeregion (AR) NOAA 11476 between 08 and 10 May 2012. Most of these ejections wereaccompanied by M-class flares. Previous works have analyzed these events separately finding acharacteristic magnetic configuration that persisted almost unchanged during the observed period.It consisted of a small rotating magnetic bipole that emerged in the middle of the globallybipolar AR. The bipole rotation was sustained along three days. Magnetic flux cancellationwas also detected along the polarity inversion line of the small bipole where minifilamentswere recurringly formed and ejected. In this work we analyze the magnetic topology of theobserved configuration identifying the location and evolution of quasi-separatrix layers (QSLs)associated to the AR and the embedded small rotating bipole, where magnetic reconnectionoccurs. Our analysis combines multiwavelength observations from AIA and HMI on board theSolar Dynamics Observatory (SDO) with force-free models of the AR. Our results show thatthe continuous rotation, injecting magnetic twist in the system, contributes to increase the freemagnetic energy in the configuration, what in combination with the observed flux cancellation,leads to conditions favouring the minifilament eruption and magnetic reconnection followedby the injection of the minifilament plasma in magnetic field lines that connect the main ARpolarities.