The effect of limited spatial resolution of stellar surface magnetic field maps on MHD wind and coronal X-ray emission models

TL;DR

This study investigates how the spatial resolution of solar surface magnetic field maps impacts the accuracy of MHD wind and coronal X-ray emission models, highlighting the importance of resolving small-scale magnetic structures.

Contribution

It demonstrates that higher spatial resolution of magnetic maps significantly influences the modeling of solar wind and X-ray emission, emphasizing the need for detailed surface magnetic data.

Findings

Wind structure is affected by small-scale magnetic features.

X-ray morphology depends on the resolution of magnetic maps.

Proper resolution of mixed polarity flux is crucial for reliable coronal models.

Abstract

We study the influence of the spatial resolution on scales of $5\deg$ and smaller of solar surface magnetic field maps on global magnetohydrodynamic solar wind models, and on a model of coronal heating and X-ray emission. We compare the solutions driven by a low-resolution Wilcox Solar Observatory magnetic map, the same map with spatial resolution artificially increased by a refinement algorithm, and a high-resolution Solar and Heliospheric Observatory Michelson Doppler Imager map. We find that both the wind structure and the X-ray morphology are affected by the fine-scale surface magnetic structure. Moreover, the X-ray morphology is dominated by the closed loop structure between mixed polarities on smaller scales and shows significant changes between high and low resolution maps. We conclude that three-dimensional modeling of coronal X-ray emission has greater surface magnetic field spatial resolution requirements than wind modeling, and can be unreliable unless the dominant mixed polarity magnetic flux is properly resolved.