Features of convection in the atmosphere layers of the solar facula

1Stodilka, MI, 1Prysiazhnyi, AI, 2Kostyk, RI
1Astronomical Observatory of Ivan Franko National University of Lviv, Lviv, Ukraine
2Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine
Kinemat. fiz. nebesnyh tel (Online) 2019, 35(6):18-33
Start Page: Solar Physics
Language: Ukrainian

According to the data of complex 2D observations on the VTT telescope of the solar facula, a 3D model of the solar atmosphere in the facular region was obtained by solving the inverse radiative transfer problem in the Ba II X 4554 A line. The magnetic field was estimated using the Stokes V-profiles of the FeI X15648A line. The influence of magnetic field on photospheric convection was investigated: spatial variations in temperature and velocities at different heights were considered. It is shown that the mutual transformation of the mechanical and thermal energy of the solar plasma into magnetic energy occurs in the layers of the middle photosphere. The integral effect of a small-scale magnetic dynamo leads to lowering the temperature and slowing down the movement of the predominant downward flows in the layers of the middle photosphere in the facular regions with a strong field (greater than 1 kG), while in the facular regions with a weak field (less than 1 kG) there is an increase in temperature and acceleration of the movement of the predominant upward flows in the layers of the middle photosphere. It is shown that the magnetic field of the facula stabilizes photospheric convection, and the small-scale magnetic dynamo causes a double temperature inversion in the photospheric layers of the facula.

Keywords: diagnostics, faculae, magnetic dynamo, photosphere, Sun

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