Magnetic reconnection in the solar atmosphere

le 27 octobre 2023, 10h45 à 12h45, Victor Réville, salle Jules Verne, OMP, site Belin

Resumé: Magnetic reconnection is a fundamental process in astrophysics. It allows converting magnetic into thermal and kinetic energy in astrophysical plasmas. In the solar atmosphere, it has been associated with solar storms, flares, and the release of energetic particles and coronal mass ejections that propagate into the interplanetary space and towards Earth. However, the detailed physics of magnetic reconnection has only recently be uncovered. Before the late 2000, theory of magnetic reconnection failed to explain the observations, in particular the fast timescales of solar flares. It is now thought that a resistive instability, the tearing mode, is at the heart of fast reconnection for most astrophysical systems, from small reconnection events that heat the solar corona, to solar flares, and even pulsar winds. In this seminar, I will review the basics of magnetic reconnection and introduce the tearing instability. I will focus on application to solar physics and in particular to its possible relation with observations of signatures made by the Parker Solar Probe and Solar Orbiter. 

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