aat Acta Astrophys. Tau. Acta Astrophysica Taurica 2712-925X Kiselev Nikolai Nikolaevich, Mosсow, settlement Moskovskii, Tat'yanin Park Str., 12, Moscow, Russia. RU 106 Magnetism and Activity of the Sun - 2024 Conference Proceedings Full electric current in active regions with different levels of flare productivity: first results Fursyak Yurii Crimean Astrophysical Observatory, Nauchny 298409 22 03 2025 6 1 24 30 12 03 2025 Copyright (c) 2026 Fursyak Y. 2026 Yurii Fursyak 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).

The study aims to analyze the magnitude and dynamics of the full electric current, as well as its components – the vertical and horizontal electric currents – in active regions (ARs) with different levels of flare productivity. To calculate the magnitude of the electric current, we used data from the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) on the spatial distribution of the magnetic field vector components at the level of the solar photosphere. Twelve ARs were studied: three ARs with low, three ARs with moderate, and six ARs with high flare productivity. Each AR was monitored within 30–35 degrees relative to the central solar meridian, which corresponds to a time interval of 3–5 days. The preliminary results are as follows: (1) In most of the considered cases, the average unsigned density of the horizontal electric current is 1.5–4.5 times greater than the density of the vertical electric current; the magnitude of the full electric current is thus determined mainly by the horizontal electric current. (2) In NOAA AR 11283 and 12297, the time intervals of several tens of hours were revealed; within these intervals the average unsigned density of the vertical electric current is approximately equal to or greater than the average unsigned density of the horizontal electric current. (3) In NOAA AR 11158 and 12673 of the analyzed sample, in which the emergence of new magnetic fluxes was recorded during the monitoring time, an increase in the magnitudes of the vertical, horizontal, and full electric currents is observed 18–20 hours before the first solar flares of high X-ray classes; the time of increase in the electric current is significantly less than the time interval of increase in the magnitude of the total unsigned magnetic flux. (4) There is no explicit relationship between the magnitude of the full electric current and the flare productivity of an AR determined by the flare index. (5) The highest absolute values of the full electric current density are characteristic of ARs with moderate flare productivity.

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