Evolution of Magnetic Field in AR 11944 and the 7 January 2014 X1.2 Flare

Abstract:

NOAA AR 11944 is a fast evolving, complex active region, producing seven M-class and one X-class flares during its disk passage. The X-class flare, occurred at 18:32 UT 7 January 2014, was associated with a halo coronal mass ejection (CME). With vector magnetic field data taken by HMI/SDO, we study evolution of magnetic field in the active region, search for possible triggering of the X-class flare, and explore property of magnetic structure and topology in both small scale and large scale. We also examine impact of an emerging active region AR 11946 at the opposite hemisphere to the global structure of magnetic field, and study potential connectivity with AR 11944. Relationship between property of this event and the magnetic field in AR 11944 is also explored.