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arXiv · 2106.01461

Are the Magnetic Fields Radial in the Solar Polar Region?

Xudong Sun·Yang Liu·Ivan Milić·Ana Belén Griñón Marín
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Abstract

We investigate the orientation of the photospheric magnetic fields in the solar polar region using observations from the Helioseismic and Magnetic Imager (HMI). Inside small patches of significant polarization, the inferred magnetic field vectors at $1''$ scale appear to systematically deviate from the radial direction. Most tilt towards the pole; all are more inclined toward the plane of sky compared to the radial vector. These results, however, depend on the "filling factor" $f$ that characterizes the unresolved magnetic structures. The default, uninformative $f\equiv1$ for HMI will incur larger inclination and less radial fields than $f<1$. The observed trend may be a systematic bias inherent to the limited resolution.

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Xudong Sun, Yang Liu, Ivan Milić, Ana Belén Griñón Marín. 2021-06-02. Are the Magnetic Fields Radial in the Solar Polar Region?. https://arxiv.org/abs/2106.01461

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