Dual chromospheric flows in the surroundings of a solar pore
Heading:
| 1Leiko, UM, 2Kondrashova, NN 1Astronomical Observatory of Taras Shevchenko National University of Kyiv, Kyiv, Ukraine 2Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine |
| Kinemat. fiz. nebesnyh tel (Online) 2017, 33(3):25-40 |
| https://doi.org/10.15407/kfnt2017.03.025 |
| Start Page: Solar Physics |
| Language: Russian |
Abstract: Chromospheric line-of-sight velocities in a small solar pore and its surroundings in a region of size 5" are studied. The spectropolarimetric observations were carried out with the French-Italian THEMIS telescope of the Instituto de Astrofisica de Canarias (Spaine, Tenerife). We use Hα-spectra of the active region NOAA 11024 and the spectrum of the quiet region for a comparison. Strong variations of line-of-sight velocity are revealed. At the beginning of the observations there were flows of different direction in two areas of the region under consideration. The first area included a bright point in the vicinity of the pore, and the second region covered the pore. There were the upflows in the first region and the downflows in the second one. 2.7 min after the beginning of the observations flows of the opposite direction appeared in both areas. Two distinct velocities within the same spatial resolution elements were observed in the region in length 2 Mm, the so-called dual flows. The size of the area occupied by the dual flows changed quickly. The region shifted in the direction of the pore. The velocity of the flows reached of ±25 km/s. Downflow in the first region lasted about one minute. Upward movement in the second region was gradually covered the pore and continued to the end of the observations. The resulting distribution of the velocity field can be due to a new small-scale magnetic flux emergence. |
| Keywords: active region, chromospheric line-of-sight velocities, solar pore, the Sun |
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