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arXiv · 1212.2226

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

C. Garraffo·O. Cohen·J. J. Drake·C. Downs
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Abstract

We study the influence of the spatial resolution on scales of $5°$ 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.

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C. Garraffo, O. Cohen, J. J. Drake, C. Downs. 2012-12-10. The effect of limited spatial resolution of stellar surface magnetic field maps on MHD wind and coronal X-ray emission models. https://doi.org/10.1088/0004-637x%2F764%2F1%2F32

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