Magnetic flux emergence and solar activity in an active region cluster

MANDRINI, C.H.; CRISTIANI, G.D.; LARA, A. ; MINERO-GARFIAS, A.

Conferencia; XI Conferencia Latinoamericana de Geofísica Espacial (XI COLAGE); 2018

We investigatethe violent events that occurred in November 2010 in the cluster of two activeregions (ARs), NOAA numbers 11121 and 11123, using instruments onboard theSolar Dynamics Observatory.  Starting on10 November and within one day the total magnetic flux increased by 70 \\% withthe emergence of new groups of bipoles in AR 11123 that was accompanied bystrong photospheric motions. During the flux emergence phase only very minorflares, with no associated coronal mass ejections (CMEs), were observed. Oncethe magnetic flux reached its maximum and the displacement of photospheric fluxconcentrations slowed down, flaring became more frequent with several relatedCMEs. Though magnetic flux emergence has been in general associated to flareand/or CME occurrence, for this particular set of events this does not seem tobe the case. We follow the magnetic flux evolution, identify all the flares andCMEs during 10 - 11 November, and determine the location along the magneticinversion lines of flare kernels and sites of CME initiation. We discuss theprobable origin of the discrepancy between usually accepted assumptions andthe evolution of activity in the analyzed active region cluster.