Structure of photosphere under high resolution: granules, faculae, micropores, intergranular lanes
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The fundamental small-scale structures such as granules, faculae, micropores that are observed in the solar photosphere under high resolution are discussed. As a separate constituent of the fine structure, a continuous net of dark intergranular lanes is considered. The results due to image processing of micropores and facular knots obtained on modern adaptive optics telescopes are presented. For intergranular lanes and micropores, a steady-state magnetic diffusion model is proposed, in which the horizontal-vertical plasma flows converging to a intergranular lane (and to the body of a micropore) compensate for the dissipative spreading of the magnetic flux at a given scale. A theoretical estimate of the characteristic scales of these structures in the photosphere is obtained as 20–30 km for the thickness of dark intergranular lanes (and the diameter of the thinnest magnetic tube in the solar photosphere), 200–400 km for the diameter of micropores. A model of a facular knot with the darkening core on the axis, which physically represents a micropore, stabilizing the entire magnetic configuration over a time interval of up to 1 day, is briefly described.
KeywordsSun Photosphere Magnetic field Granules Micropores Faculae Intergranular lanes
We are grateful to the teams of Goode Solar Telescope (Big Bear Solar Observatory) and Swedish 1-meter Solar Telescope (SST) for allowing us to use the observational data. We thank the referee of the article for helpful and well-meaning comments.
This work was supported by the Russian National Science Foundation (project 15-12-20001), the Russian Foundation for Basic Research (project 18-02-00168) and the Program KP19-270.
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