Advances in Astrophysics

Download PDF (3573.4 KB) PP. 103 - 116 Pub. Date: May 1, 2017

DOI: 10.22606/adap.2017.22005

• Cristiana Dumitrache^*
  Astronomical Institute of Romanian Academy, Str. Cutitul de Argint 5, 040557 Bucharest, Romania

We have performed numerical magnetohydrodynamic (MHD) simulations of two closed active regions (AR). The input magnetic field values were the coronal magnetic field computed as extrapolation coronal from observations of the photospheric magnetic field. The studied active regions, NOAA AR12565 and AR12567, were registered as different bipolar region. Our investigation, the 3D coronal extrapolations, as well as the numerical MHD experiments, revealed that actually they evolved together as a quadrupolar active region. The second region emerged later under the loops system of AR12565 and separated from this one. A natural current sheet formed between then and it plays an important role in the explosive events (flares and coronal mass ejections) occurrence.

Solar physics, numerical simulations, active regions, magnetogram, solar observations.

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