Analysis of a long-duration AR throughout five solar rotations: Magnetic properties and ejective events

IGLESIAS, FRANCISCO A.; CREMADES, HEBE; MERENDA, LUCIANO A.; MANDRINI, CRISTINA H.; LÓPEZ, FERNANDO M.; LÓPEZ FUENTES, MARCELO C.; UGARTE-URRA, IGNACIO

ADVANCES IN SPACE RESEARCH

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2020

0273-1177

Coronal mass ejections (CMEs), which are among the most violent solar eruptions(having mass of order 1012 g and speeds of order 1000 kms􀀀1),are a major driver of space weather and can thus aect diverse human technologies.Dierent processes have been proposed to explain the initiationand release of CMEs from solar active regions (ARs), without reaching consensuson which is the predominant scenario, and thus rendering impossibleto accurately predict when a CME is going to erupt from a given AR. Toinvestigate AR properties that favor CMEs production, we employ multispacecraftdata to analyze a long duration AR (NOAA 11089, 11100, 11106, 11112 and 11121) throughout its complete lifetime, spanning ve Carringtonrotations from July to November 2010. We use data from the Solar DynamicsObservatory to study the evolution of the AR magnetic propertiesduring the ve near-side passages, and a proxy to follow the magnetic uxchanges when no magnetograms are available, i.e. during far-side transits.The ejectivity is studied by characterizing the angular widths, speeds andmasses of 108 CMEs that we associated to the AR, when examining a 124-day period. Such an uninterrupted ejectivity tracking was possible thanksto the mulit-viewpoint images provided by the Solar-Terrestrial RelationsObservatory and Solar and Heliospheric Observatory in a quasi-quadratureconguration. Given the substantial number of ejections studied, we use astatistical approach instead of a single-event analysis. We found three periodsof very high ejective activity and two periods with no CMEs that arepreceded or accompanied by characteristic changes in the AR magnetic flux, free magnetic energy and/or presence of electric currents. Our large sampleof CMEs and long term study of a single AR, provide further evidence thatcorrelates AR magnetic activity to CME production.