Possible evidences of extremely strong magnetic fields observed in a sunspot using spectro-polarimetry around the D3 line
Рубрика:
| Lozitsky, VG |
| Kinemat. fiz. nebesnyh tel (Online) 2025, 41(6):58-72 |
| https://doi.org/10.15407/kfnt2025.06.058 |
| Язык: Ukrainian |
Аннотация: The main goal of our research is to search for super-strong magnetic fields in ’quiet’ sunspots without flares. Our method is based on Stokes V spectro-polarimetry in a wide spectral range – from –5 nm to +2.5 nm relative to the D3 He I line. The objects of the study are two simple sunspots of 35...40 Mm in diameter, which were observed on July 17 and 24, 2023, close to the disk center, with the heliocentric angles of about 18 degrees. The novelty of our study: in the second sunspot, we found characteristic spectral features at approximately –1.88 and –0.84 nm from D3 He I line, which can be strongly split Zeeman sigma components of the mentioned line for the following reasons: (a) their Stokes V signs are opposite, and amplitudes reach 5 %, significantly exceeding the measurement errors, (b) amplitudes of ’blue’ and ’red’ peaks change synchronously along the slit, (c) spectral profiles of both peaks are similar in shape and mutually anti-symmetrical. If the indicated spectral features are interpreted as a manifestation of a joint action of Zeeman and Doppler effects, then we can assume the existence of very fine-structured (spatially unresolved) jets in the sunspot, in which the magnetic field’s order of magnitude is 105 G, and the ascending plasma velocity reaches 700 km/s. If this interpretation is confirmed, it will be possible to take a new look onto two current problems in heliophysics: anomalously fast rotation of the corona at low latitudes and arising of superstrong magnetic fields in the chromosphere and corona. |
| Ключевые слова: magnetic fields, spectro-polarimetry in D3 line, Sun, sunspots, super-strong fields |
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