Investigating Solar Wind Outflows from Open-Closed Magnetic Field Structures Using Coordinated Solar Orbiter and Hinode Observations

TL;DR

This study combines Solar Orbiter and Hinode observations to analyze solar wind outflows from different magnetic structures, revealing how plasma properties and wind speeds vary with altitude and magnetic configuration.

Contribution

It provides new insights into the origins and properties of solar wind from open-field corridors and coronal holes using coordinated multi-instrument observations.

Findings

Higher electron densities in open-field corridors compared to coronal holes.

No correlation between wind speed and magnetic expansion factor in corridors.

Reconnection may influence solar wind variability at higher altitudes.

Abstract

ESA/NASA's Solar Orbiter (SO) allows us to study the solar corona at closer distances and from different perspectives, which helps us to gain significant insights into the origins of the solar wind. In this work, we present the analysis of solar wind outflows from two locations: a narrow open-field corridor and a small, mid-latitude coronal hole. These outflows were observed off-limb by the Metis coronagraph onboard SO and on-disk by the Extreme Ultraviolet Imaging Spectrometer (EIS) onboard Hinode. Magnetic field extrapolations suggest that the upflow regions seen in EIS were the sources of the outflowing solar wind observed with Metis. We find that the plasma associated with the narrow open-field corridor has higher electron densities and lower outflow velocities compared to the coronal hole plasma in the middle corona, even though the plasma properties of the two source regions in the low corona are found to be relatively similar. The speed of solar wind from the open-field corridor also shows no correlation with the magnetic field expansion factor, unlike the coronal hole. These pronounced differences at higher altitudes may arise from the dynamic nature of the low-middle corona, in which reconnection can readily occur and may play an important role in driving solar wind variability.