Abstract


  MODELLING REPEATEDLY FLARING DELTA SUNSPOTS

  P. Chatterjee, Indian Institute of Astrophysics, piyali.chatterjee@iiap.res.in
  M. Carlsson, ITA, UiO, Oslo, mats.carlsson@astro.uio.no
  V. Hansteen, ITA, UiO, Oslo, viggo.hansteen@astro.uio.no

Active regions (AR) appearing on the surface of the Sun are classified into alpha, beta, gamma, and delta by the rules of the Mount Wilson Observatory, California on the basis of their topological complexity. Amongst these, the delta-sunspots are known to be super-active and produce the most X-ray flares. Here, we present results from a simulation of the Sun by mimicking the upper layers and the corona, but starting at a more primitive stage than any earlier treatment. We find that this initial state consisting of only a thin sub-photospheric magnetic sheet breaks into multiple flux-tubes which evolve into a colliding-merging system of spots of opposite polarity upon surface emergence, similar to those often seen on the Sun. The simulation goes on to produce many exotic delta-sunspot associated phenomena: repeated flaring in the range of typical solar flare energy release and ejective helical flux ropes with embedded cool-dense plasma filaments resembling solar coronal mass ejections.