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Seething Horizontal Magnetic Fields in the Quiet Solar Photosphere

J. W. Harvey·D. Branston·C. J. Henney·C. U. Keller·the SOLIS Team·the GONG Team
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Abstract

The photospheric magnetic field outside of active regions and the network has a ubiquitous and dynamic line-of-sight component that strengthens from disk center to limb as expected for a nearly horizontal orientation. This component shows a striking time variation with an average temporal rms near the limb of 1.7 G at ~3" resolution. In our moderate resolution observations the nearly horizontal component has a frequency variation power law exponent of -1.4 below 1.5 mHz and is spatially patchy on scales up to ~15 arcsec. The field may be a manifestation of changing magnetic connections between eruptions and evolution of small magnetic flux elements in response to convective motions. It shows no detectable latitude or longitude variations.

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J. W. Harvey, D. Branston, C. J. Henney, C. U. Keller, the SOLIS Team, the GONG Team. 2007-02-15. Seething Horizontal Magnetic Fields in the Quiet Solar Photosphere. https://doi.org/10.1086/518036

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