Study of the problem of open magnetic flux based on the data from various observatories

Introduction. The magnetic field of solar corona is directly related to solar activity, including flares and coronal mass ejections. It is also directly linked to the formation of the constantly outgoing streams of solar plasma, known as the solar wind. Specifically, solar wind sources are concentrated in regions of the so-called open magnetic field. The structure of field, location, and shape influence the speed of the plasma streams. Therefore, it is crucial to compare the calculated open magnetic flux with the value obtained from direct observations.

Goal. Compare the results of magnetic flux calculations with the data obtained from various observatories

Materials and methods. In this paper, the data validation is carried out using photospheric magnetic maps constructed using ground-based telescopes, the Kislovodsk Astronomical Station and GONG, in 2024.

Results and discussion. Calculations have shown that the discrepancy between the observed and calculated open magnetic flux is significant, typical for the maximum of solar activity.

Conclusion. Apparently, the accuracy of the potential model is not sufficient to obtain an adequate coronal magnetic field that would allow the open magnetic flux to be taken into account fully.

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