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arXiv · 1004.1885

Magnetic bright points in the quiet Sun

J. Sanchez Almeida·J. A. Bonet·B. Viticchie·D. Del Moro
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Abstract

We present a visual determination of the number of bright points (BPs) existing in the quiet Sun, which are structures though to trace intense kG magnetic concentrations. The measurement is based on a 0.1 arcsec angular resolution G-band movie obtained with the Swedish Solar Telescope at the solar disk center. We find 0.97 BPs/Mm^2, which is a factor three larger than any previous estimate. It corresponds to 1.2 BPs per solar granule. Depending on the details of the segmentation, the BPs cover between 0.9% and 2.2% of the solar surface. Assuming their field strength to be 1.5 kG, the detected BPs contribute to the solar magnetic flux with an unsigned flux density between 13 G and 33 G. If network and inter-network regions are counted separately, they contain 2.2 BPs/Mm^2 and 0.85 BPs/Mm^2, respectively.

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J. Sanchez Almeida, J. A. Bonet, B. Viticchie, D. Del Moro. 2010-04-12. Magnetic bright points in the quiet Sun. https://doi.org/10.1088/2041-8205%2F715%2F1%2Fl26

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