The 2013 February 17 sunquake in the context of the active region's magnetic field configuration

Green, L. M.; Valori, G.; Zuccarello, F. P.; Zharkov, S.; Matthews, S. A.; Guglielmino, S. L.

Abstract

© 2017. The American Astronomical Society. All rights reserved. Sunquakes are created by the hydrodynamic response of the lower atmosphere to a sudden deposition of energy and momentum. In this study, we investigate a sunquake that occurred in NOAA active region 11675 on 2013 February 17. Observations of the corona, chromosphere, and photosphere are brought together for the first time with a nonlinear force-free model of the active region's magnetic field in order to probe the magnetic environment in which the sunquake was initiated. We find that the sunquake was associated with the destabilization of a flux rope and an associated M-class GOES flare. Active region 11675 was in its emergence phase at the time of the sunquake and photospheric motions caused by the emergence heavily modified the flux rope and its associated quasi-separatrix layers, eventually triggering the flux rope's instability. The flux rope was surrounded by an extended envelope of field lines rooted in a small area at the approximate position of the sunquake. We argue that the configuration of the envelope, by interacting with the expanding flux rope, created a “magnetic lens” that may have focussed energy on one particular location of the photosphere, creating the necessary conditions for the initiation of the sunquake.

Citation

Green, L. M., Valori, G., Zuccarello, F. P., Zharkov, S., Matthews, S. A., & Guglielmino, S. L. (2017). The 2013 February 17 sunquake in the context of the active region's magnetic field configuration. The Astrophysical journal, 849(1), Article 40. https://doi.org/10.3847/1538-4357/aa8db6

• Journal Article Type: Article
• Acceptance Date: Aug 25, 2017
• Online Publication Date: Oct 27, 2017
• Publication Date: Nov 1, 2017
• Deposit Date: Mar 8, 2018
• Publicly Available Date: Mar 19, 2018
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 849
• Issue: 1
• Article Number: 40
• DOI: https://doi.org/10.3847/1538-4357/aa8db6
• Keywords: Space and Planetary Science; Astronomy and Astrophysics
• Public URL: https://hull-repository.worktribe.com/output/724388
• Publisher URL: http://iopscience.iop.org/article/10.3847/1538-4357/aa8db6/meta
• Related Public URLs: http://discovery.ucl.ac.uk/1574331/
• Contract Date: Mar 8, 2018