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

Abstract

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 17 February 2013. Observations of the corona, chromosphere and photosphere are brought together for the first time with a non-linear 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 in one particular location the photosphere, creating the necessary conditions for the initiation of the sunquake.

20 pages, 16 Figures. Some figures have lower resolution than published version

References in corpus (6)

• On the origin of 3 seismic sources in the proton-rich flare of October 28, 2003
• On the 2012 October 23 circular ribbon flare: emission features and magnetic topology
• Propagation of Alfvénic Waves From Corona to Chromosphere and Consequences for Solar Flares
• Quasi-Static 3D-Magnetic Field Evolution in Solar Active Region NOAA 11166 Associated with X1.5 Flare
• The Cause of Photospheric and Helioseismic Responses to Solar Flares: High-Energy Electrons or Protons?
• Energy Release and Initiation of Sunquake in C-class Flare

Cited by in corpus (4)

• Decoding the Pre-Eruptive Magnetic Field Configurations of Coronal Mass Ejections
• Non-equilibrium Flux Rope Formation by Confined Flares Preceding a Solar Coronal Mass Ejection
• A Possible Selection Rule for Flares Causing Sunquakes
• Flare Induced Sunquake Signatures in the Ultraviolet as Observed by the Atmospheric Imaging Assembly