aat Acta Astrophys. Tau. Acta Astrophysica Taurica 2712-925X Kiselev Nikolai Nikolaevich, Mosсow, settlement Moskovskii, Tat'yanin Park Str., 12, Moscow, Russia. RU 68 10.34898/aat.vol5.iss1.pp1-4 Research articles Boundary conditions and MHD equilibrium of force-free magnetic flux ropes Tsap Yurii Kopylova Yuliya Crimean Astrophysical Observatory, Nauchny 298409 Central Astronomical Observatory at Pulkovo, Pulkovskoe ave. 65/1, St. Petersburg 196140, Russia 28 03 2024 5 1 1 4 27 03 2024 Copyright (c) 2026 Tsap Y., Kopylova Y. 2026 Yurii Tsap, Yuliya Kopylova 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).

We perform an analysis of the magnetohydrodynamic (MHD) equilibrium of force-free magnetic flux ropes taking into account boundary conditions. It was shown that the use of the generating function to solve the MHD equilibrium equation of a force-free flux rope can lead to incorrect conclusions. The continuity condition of the tangential component of the electric field on the boundary surface in the ideal magnetohydrodynamics approximation is always satisfied and does not require separate consideration.

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