Magnetic field configuration in a flaring active region

Author(s)

Palacios, J. ; Balmaceda, L. A. ; Vieira, L. E. ; Nagendra, KN ; Bagnulo, S ; Centeno, R ; Gonzalez, MJM

• Document type: Journal article
• Source: POLARIMETRY: FROM THE SUN TO STARS AND STELLAR ENVIRONMENTS; v. 10, n. 305, p. 5-pg., 2015-01-01.

Abstract

The Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) provides continuous monitoring of the Sun's vector magnetic field through full-disk photospheric data with both high cadence and high spatial resolution. Here we investigate the evolution of AR 11249 from March 6 to March 7, 2012. We make use of HMI Stokes imaging, SDO/SHARPs, the HMI magnetic field line-of-sight (LOS) maps and the transverse components of the magnetic field as well as LOS velocity maps in order to detect regions with significant flux emergence and/or cancellation. In addition, we apply the Local Correlation Tracking (LCT) technique to the total and signed magnetic flux data and derive maps of horizontal velocity. From this analysis, we were able to pinpoint localized shear regions (and a shear channel) where penumbrae and pore formation areas, with strong linear polarization signals, are stretched and squeezed, showing also important downflows and upflows. We have also utilized Hinode/SP data and compared them to the HMI-SHARPs and the HMI-Stokes spectrograms. The aforementioned shear channel seems to correspond well with the X-class flare main channel of March 7 2012, as observed in AIA/SDO 171, 304 and 1600 angstrom. (AU)

• FAPESP's process: 13/03085-7 - Solar surface sources of intense geomagnetic storms in solar cycle 24
• Grantee: Laura Antonia Balmaceda
• Support Opportunities: Scholarships in Brazil - Post-Doctoral