Magnetic and velocity field variations in the active regions NOAA 10486 and NOAA 10488
Abstract
We study the magnetic and velocity field evolution in the two magnetically complex active regions NOAA 10486 and NOAA 10488 observed during October-November 2003. We have used the available data to examine net flux and Doppler velocity time profiles to identify changes associated with evolutionary and transient phenomena. In particular, we report detection of rapid moving features observed in NOAA 10486 during the maximum phase of the X17.2/4B superflare of October 28, 2003. The velocity of this moving feature is estimated around 40 km/s, i.e., much greater than the usual Hα flare-ribbons' separation speed of 3-10 km/s, but similar to the velocity of seismic waves, i.e., ∼45 km/s reported earlier by Kosovichev & Zharkova (1998).
- Publication:
-
Journal of Astrophysics and Astronomy
- Pub Date:
- March 2008
- DOI:
- 10.1007/s12036-008-0013-2
- Bibcode:
- 2008JApA...29..103M