Abstract


  TWO-PHASE FILAMENT ERUPTION IN ASSOCIATION WITH FLUX CANCELLATIONS AND CONTRACTION OF CORONAL LOOP DYNAMICS AS OBSERVED BY AIA/SDO

  S. Dhara , Indian Institute of Astrophysics, sajal@iiap.res.in
  B. Ravindra, Indian Institute of Astrophysics, ravindra@iiap.res.in
  R. Banyal , Indian Institute of Astrophysics, banyal@iiap.res.in

Using multi wavelength solar atmospheric data we investigated filament eruptions associated with the active region NOAA 11444 occurred on March 27 2012. The filament was inverse 'J'shaped and located above the polarity inversion line. The whole filament was erupted in two different phases. In the first phase of eruption, the filament has started activation at $\sim$ 01:56 UT on March 27. In the second phase of eruption the other part of it started activation at $\sim$04:20 UT on the same day. Prior to first activation at $\sim$01:56 UT, a pre-eruption brightening in coronal emission was seen close to the eastern end of the filament. A bright flow was also observed in EUV along the length of the filament at $\sim$01:57 UT that moved about 39 Mm towards west side along the filament within 7 min. Beneath coronal brightening region in the photosphere, the continuous motion of the opposite polarity features moving towards each other resulted in cancellation of magnetic field. This cancellation was observed for a few hours near the magnetic neutral line. Later, the postflare loops in the western side were seen to be contracting while those in eastern side were seen to be expanding towards higher heights. The northern side of the remaining filament ejected soon after the collapse of coronal loop in the second phase of eruption. Here we will present the important morphological changes in and around the filament prior to the eruption and the possible triggering mechanism of the first and second part of the filament.