Coronal Magnetic Field Topology From Total Solar Eclipse Observations
| Autor: | Shadia Rifai Habbal, Miloslav Druckmüller, Benjamin Boe |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Physics
Photosphere 010504 meteorology & atmospheric sciences Solar eclipse Field line Coronal hole FOS: Physical sciences Astronomy and Astrophysics Solar radius Topology 01 natural sciences Solar cycle Magnetic field Solar wind Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science 0103 physical sciences Physics::Space Physics Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics 010303 astronomy & astrophysics Solar and Stellar Astrophysics (astro-ph.SR) 0105 earth and related environmental sciences |
| DOI: | 10.48550/arxiv.2004.08970 |
| Popis: | Measuring the global magnetic field of the solar corona remains exceptionally challenging. The fine-scale density structures observed in white light images taken during Total Solar Eclipses (TSEs) are currently the best proxy for inferring the magnetic field direction in the corona from the solar limb out to several solar radii (Rs). We present, for the first time, the topology of the coronal magnetic field continuously between 1 and 6 Rs, as quantitatively inferred with the Rolling Hough Transform (RHT) for 14 unique eclipse coronae that span almost two complete solar cycles. We find that the direction of the coronal magnetic field does not become radial until at least 3 Rs, with a high variance between 1.5 and 3 Rs at different latitudes and phases of the solar cycle. We find that the most non-radial coronal field topologies occur above regions with weaker magnetic field strengths in the photosphere, while stronger photospheric fields are associated with highly radial field lines in the corona. In addition, we find an abundance of field lines which extend continuously from the solar surface out to several solar radii at all latitudes, regardless of the presence of coronal holes. These results have implications for testing and constraining coronal magnetic field models, and for linking in situ solar wind measurements to their sources at the Sun. Comment: 18 pages, 11 figures, accepted for publication in ApJ |
| Databáze: | OpenAIRE |
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