Do the sunspot umbra magnetic field characteristics vary during flares and coronal mass ejections?
Abstract
We found variations in the sunspot umbra magnetic field characteristics within active regions (ARs), where eruptive events (solar flares, coronal mass ejections (CMEs)) originated. The behavior of the maximum of the module of magnetic induction B_{max}, the minimum inclination of the magnetic field lines to the normal α_{min} and their averages values (B_{mean} and α_{mean}) within umbrae were analyzed. A change of behavior of the magnetic field parameters after flare beginning is observed. Thus, for example, during 3 hours before a solar flare/eruption the _min angle in umbrae of the sunspots closely located to the "feet" of an eruptive rope is increasing to a larger values (4° through 10°). Later a strong decreasing over 1 _ 3 hours after the flare onset to small values (≤1°) is observed. At the same time the α_{mean} angle varies essentially more weakly. This implies that the magnetic tube from the umbra of such sunspots after the flare onset deflects from the initial position almost as a whole, i.e. without essential transformation in the distribution of the magnetic field lines inside the tube.
- Publication:
-
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018
- Bibcode:
- 2018cosp...42E3795Z