Solar faculae: microturbulence as an indicator of inclined magnetic fields
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| 1Stodilka, MI, 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) 2020, 36(4):3-18 |
| https://doi.org/10.15407/kfnt2020.04.003 |
| Start Page: Solar Physics |
| Language: Ukrainian |
Abstract: According to the observations of the solar facula in the Ba II λ 455.403 nm line, a 3D model of the facula area was obtained by solving the inverse nonequilibrium radiative transfer problem. The fine structure of the field of unresolved velocities (microturbulence) was studied. In the layers of the upper photosphere, new turbulent structures are formed, they are localized mainly between ascending and descending flows with the formation of ring-shaped structures of increased turbulence around these flows. We proposed a mechanism of the magnetic anisotropy of microturbulent velocity (small-scale eddy-like plasma movements occur predominantly in planes perpendicular to the magnetic field), which makes it possible to explain the height dependence of the field of unresolved velocities. Anisotropy of microturbulence starts to appear in the lower photospheric layers outside ascending and descending flows, while inside these flows it takes place in higher layers. An increase of microturbulence in the layers of the upper photosphere and lower chromosphere in the areas between the plasma flows indicates the presence of oblique magnetic fields, which, along with the blurring of its spatial structure, indicates the existence of a magnetic canopy region. Microturbulence can be used as an additional tool for the diagnosis of oblique magnetic fields |
| Keywords: diagnostics, faculae, microturbulence, oblique magnetic fields, photosphere, Sun |
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