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SUMMARY:Net electric currents\, flares\, CMEs and the evolution of active 
 regions
DTSTART;VALUE=DATE-TIME:20230510T140500Z
DTEND;VALUE=DATE-TIME:20230510T142000Z
DTSTAMP;VALUE=DATE-TIME:20240704T115655Z
UID:indico-contribution-329@meetings.aip.de
DESCRIPTION:Speakers: Ioannis Kontogiannis (Leibniz Institute for Astrophy
 sics Potsdam (AIP) Germant)\nThe build-up of magnetic energy during flux e
 mergence\, which powers flares and coronal mass ejections (CME)\, requires
  the presence of significant amounts of volume electric currents. Measurin
 g these electric currents requires knowledge of the magnetic field vector 
 in three dimensions in the solar atmosphere. However\, systematic high-qua
 lity spectropolarimetric observations are constrained at the photosphere. 
 Thus\, only the vertical component of the electric current density\, *Jz*\
 , can be routinely calculated by means of differentiation of the photosphe
 ric magnetic field vector. In this work\, a different method\, relying on 
 image segmentation and taking into account observational and numerical err
 ors\, is employed to determine the total unsigned non-neutralized (net) el
 ectric currents\, *INN\,tot*\, injected to the corona. This quantity devia
 tes from *Jz* and is more closely associated to the development of strongl
 y sheared polarity inversion lines (PIL). It is found that *INN\,tot* is a
 t least one order of magnitude higher for flare productive active regions 
 and its temporal evolution from emergence to decay exhibits intricate stru
 cture\, owing to the interaction between opposite magnetic polarities and 
 the formation of PILs. Further relevant quantities facilitate the distinct
 ion between imminent eruptive and confined major flares and they are stron
 gly correlated with the kinematic characteristics of subsequent CMEs. Thes
 e quantities are examined during the emergence and pre-eruptive evolution 
 of active regions and their association with the magnetic complexity of ac
 tive regions.\n\nhttps://meetings.aip.de/event/24/contributions/329/
LOCATION:Haus H\, Telegrafenberg
URL:https://meetings.aip.de/event/24/contributions/329/
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