Simulating the formation of a sigmoidal flux rope in AR10977 from SOHO/MDI magnetograms

Gordon Peter Samuel Gibb, Duncan Hendry Mackay, Lucie Green, Karen Alison Meyer

Research output: Contribution to journalArticlepeer-review

54 Citations (Scopus)
1 Downloads (Pure)


The modeling technique of Mackay et al. is applied to simulate the coronal magnetic field of NOAA active region AR10977 over a seven day period (2007 December 2-10). The simulation is driven with a sequence of line-of-sight component magnetograms from SOHO/MDI and evolves the coronal magnetic field though a continuous series of non-linear force-free states. Upon comparison with Hinode/XRT observations, results show that the simulation reproduces many features of the active region's evolution. In particular, it describes the formation of a flux rope across the polarity inversion line during flux cancellation. The flux rope forms at the same location as an observed X-ray sigmoid. After five days of evolution, the free magnetic energy contained within the flux rope was found to be 3.9 × 1030 erg. This value is more than sufficient to account for the B1.4 GOES flare observed from the active region on 2007 December 7. At the time of the observed eruption, the flux rope was found to contain 20% of the active region flux. We conclude that the modeling technique proposed in Mackay et al.—which directly uses observed magnetograms to energize the coronal field—is a viable method to simulate the evolution of the coronal magnetic field.

Original languageEnglish
Article number71
Number of pages14
JournalAstrophysical Journal
Issue number2
Early online date29 Jan 2014
Publication statusPublished - 20 Feb 2014


  • Sun: corona
  • Sun: coronal mass ejections (CMEs)
  • Sun: flares
  • Sun: X-rays, gamma rays


Dive into the research topics of 'Simulating the formation of a sigmoidal flux rope in AR10977 from SOHO/MDI magnetograms'. Together they form a unique fingerprint.

Cite this