The next CmPA, plasma astrophysics (KULeuven) seminar is given by Luis Linan on 3 June 2021 at 2:00 PM on the zoom-platform.
Title: A new marker of solar eruptivity based on an unfathomed magnetic helicity decomposition
Abstract:
The spectacular phenomena that are solar eruptions can impact human infrastructures. As we become more and more sensitive to solar activity because of the technological evolution of our society, solar forecasting is a growing economic stake.
Luis aims to establish deterministic criteria allowing reliable predictions of solar eruptions and was particularly focused on the study of the properties of an unfathomed decomposition of magnetic helicity: the non-potential magnetic helicity (linked to the magnetic field carrying electric currents) and the volume-threading magnetic helicity (containing the rest of the information).
Using diverse series of parametric 3D MHD simulations of eruptions, resulting either from line-tied boundary forcing or from flux emergence, it was shown that a quantity based on this decomposition was able to efficiently characterize the eruptivity of the magnetic systems.
Afterwards, the production of 3D reconstructions of the coronal magnetic field obtained from a set of photospheric observations allowed me to confirm that the new criteria can indeed mark the eruptive potential of solar active regions. Special care should however be given to the reliability of the measurement method used since the criteria cannot be correctly determined when the reconstructed magnetic field does not respect the solenoidal property.
The zoom-link will follow.
