aat Acta Astrophys. Tau. Acta Astrophysica Taurica 2712-925X Kiselev Nikolai Nikolaevich, Mosсow, settlement Moskovskii, Tat'yanin Park Str., 12, Moscow, Russia. RU 76 Magnetism and activity of the Sun and stars – 2021 Conference proceedings Electric currents in unipolar active regions with different magnetic flux decay rates in sunspots Fursyak Yurii Plotnikov Andrei Abramenko Valentina Crimean Astrophysical Observatory, Nauchny, 298409 Crimean Astrophysical Observatory, Nauchny, 298409 Crimean Astrophysical Observatory, Nauchny, 298409 23 06 2024 5 2 6 12 16 06 2024 Copyright (c) 2026 Fursyak Y., Plotnikov A., Abramenko V. 2026 Yurii Fursyak, Andrei Plotnikov, Valentina Abramenko The metadata for this submission is licensed under a Creative Commons Attribution 4.0 International License. Copyright and publishing rights for texts published in Acta Astrophysica Taurica is retained by the authors, with first publication rights granted to the journal.Texts are free to use with proper attribution and link to the licensing (Creative Commons Attribution 4.0 International).

Using the magnetographic data of the Helioseismic and Magnetic Imager (HMI) instrument on board the Solar Dynamics Observatory (SDO), we calculated parameters of the magnetic field and electric currents for unipolar active regions (ARs) with low (≤ 2.1 × 10 19 Mx h −1 ; in total, 11 ARs were analyzed) and high (≥ 7.0 × 10 19 Mx h −1 , 5 ARs were analyzed) magnetic flux decay rates in sunspots. We obtained the following results: 1) the stronger the local (small-scale) electric currents in the vicinity of a unipolar sunspot, the faster its decaying; 2) the distributed (global, large-scale) electric current around the rapidly decaying sunspots is practically zero. There cannot be expected a stabilizing effect on the decay of a sunspot; 3) in four cases of slowly decaying sunspots, a nonzero distributed electric current of up to 5.0 × 10 12 A was detected. Perhaps such electric current can have a stabilizing effect on the decay of a sunspot. Thus, our findings indicate that strong electric currents of small scales have a rather destructive effect on a sunspot, and the presence of large-scale currents can stabilize it. However, this mechanism seems not to be the only one and dominant in the processes of stabilization of unipolar sunspots.

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