Abnormal Stokes profiles in the region of chromospheric dual flows in the surroundings of a solar pore. I. Observation
Heading:
| 1Kondrashova, NN 1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine |
| Kinemat. fiz. nebesnyh tel (Online) 2018, 34(2):3-24 |
| https://doi.org/10.15407/kfnt2018.02.003 |
| Start Page: Solar Physics |
| Language: Russian |
Abstract: The results of the analysis of the full Stokes profiles of the photospheric lines Fe I λ 630.15 and Fe I λ 630.25 nm in a region of chromospheric dual flows in the vicinity of a small pore are presented. The analysis is based on the spectropolarimetric observations of the active region NOAA 11024 with the French-Italian telescope THEMIS (Heliographic Telescope for the Study of the Magnetism and Instabilities on the Sun), operated on the island of Tenerife in the Spanish Observatorio del Teide of the Instituto de Astrofisica de Canarias. The temporal variation of the high-resolution Stokes parameters I, Q, U, V of the photospheric lines was considered for each pixel studied. The observed Stokes profiles show variety of shapes. Most of the Stokes profiles Q, U, and V have complex shape. The amplitude and the shape of the Stokes profiles were changing quickly during the observations. The dual chromospheric flows have appeared in the region of abnormal Stokes profiles. The change of the polarity of the photospheric magnetic field took place during the observations in the region of a bright chromospheric point. The evidence of an emergence of a new small-scale magnetic flux of opposite polarity is obtained. This could lead to the magnetic reconnection, appearance of the dual chromospheric flows and occurrence of a microflare. |
| Keywords: active regions, magnetic fields, photosphere, spectropolarimetry, the Sun |
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