The Magnetic Structure of Solar Prominence Cavities: New Observational Signature Revealed by Coronal Magnetometry
Abstract
The Coronal Multi-Channel Polarimeter (CoMP) obtains daily full-Sun above-the-limb coronal observations in linear polarization, allowing, for the first time, a diagnostic of the coronal magnetic field direction in quiescent prominence cavities. We find that these cavities consistently possess a characteristic "lagomorphic" signature in linear polarization indicating twist or shear extending up into the cavity above the neutral line. We demonstrate that such a signature may be explained by a magnetic flux-rope model, a topology with implications for solar eruptions. We find corroborating evidence for a flux-rope structure in the pattern of concentric rings within cavities seen in CoMP line-of-sight velocity.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 2013
- DOI:
- 10.1088/2041-8205/770/2/L28
- arXiv:
- arXiv:1304.7388
- Bibcode:
- 2013ApJ...770L..28B
- Keywords:
-
- Sun: corona;
- Sun: filaments;
- prominences;
- Sun: infrared;
- Sun: magnetic topology;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- submitted to The Astrophysical Journal Letters