Investigating the Relationship Between Physical Properties and Spatial Irregularities at Coronal Hole Boundaries.
Nawin Ngampoopun1,2, David M Long3,4, Lucie M Green2
1Max Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany.
Solar Physics
|May 25, 2026
Summary
Coronal hole boundaries, where open and closed magnetic fields meet, influence solar wind. This study found leading boundaries have higher temperatures and smoother lines due to organized magnetic loops compared to trailing boundaries.
Area of Science:
- Solar Physics
- Magnetohydrodynamics
- Plasma Physics
Background:
- Coronal hole boundaries are critical interfaces between closed and open magnetic fields in the solar atmosphere.
- These regions are sites of fundamental processes like magnetic reconnection, driving solar wind and magnetic field restructuring.
Purpose of the Study:
- To investigate the physical properties of a large low-latitude coronal hole boundary.
- To compare the leading and trailing boundaries of the coronal hole.
Main Methods:
- Differential Emission Measure (DEM) analysis to determine plasma properties.
- Correlation dimension mapping to quantify boundary irregularities.
Main Results:
- The leading boundary exhibits higher average plasma temperature and a stronger, more unipolar magnetic field.
- The leading boundary is characterized by a smoother line compared to the trailing boundary.
- Differences are linked to local magnetic field configurations: organized loops at the leading edge versus dispersed bipoles at the trailing edge.
Conclusions:
- The surrounding magnetic field structure and magnetic reconnection dynamics significantly influence coronal hole boundary properties.
- Leading and trailing boundaries display distinct characteristics attributed to their unique magnetic field configurations.
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