Mapping the Sun's coronal magnetic field using the Zeeman effect

TL;DR

This paper presents the first detailed maps of the Sun's coronal magnetic field using the Zeeman effect, providing new insights into coronal physics and aiding space weather prediction.

Contribution

It introduces a novel observational method leveraging large aperture coronagraphy to map coronal magnetic fields via polarized spectra at 1074 nm.

Findings

Detection of Zeeman signatures in coronal spectra

Comparison with magnetohydrodynamic models shows valuable constraints

Enhanced understanding of coronal magnetic field structure

Abstract

Regular remote sensing of the magnetic field embedded within the million-degree solar corona is severely lacking. This reality impedes fundamental investigations of the nature of coronal heating, the generation of solar and stellar winds, and the impulsive release of energy into the solar system via flares and other eruptive phenomena. Resulting from advancements in large aperture solar coronagraphy, we report unprecedented maps of polarized spectra emitted at 1074 nm by Fe+12 atoms in the active corona. We detect clear signatures of the Zeeman effect that are produced by the coronal magnetic field along the optically thin path length of its formation. Our comparisons with global magnetohydrodynamic models highlight the valuable constraints that these measurements provide for coronal modeling efforts, which are anticipated to yield subsequent benefits for space weather research and forecasting.