Title: From the pre-eruption state in the Sun to the propagation of eruption products in the inner heliosphere and beyond: connecting some dots
This seminar is organised by KU Leuven's Center for mathematical Plasma-Astrophysics (CmPA).
Speaker: Manolis K. Georgoulis
Abstract: A staggering amount of literature is devoted to deciphering the poorly understood pre-eruption state in the low solar corona, from active region-spawned eruptions to the stealthy coronal mass ejections jettisoning from the quiet Sun. Naturally, focus falls on the most energetic of these events due to their capital significance in modulating, in essence morphing, the bulk of space weather in the solar system. We recount a number of works, not necessarily to provide a review, but to present an incomplete collage of understanding of the pre-eruption state in the minority of solar active regions that do erupt. The lack of knowledge of the magnetic field components above the photosphere impedes this forensic work but the active-region photosphere, in spite of line-tying, seems to sustain an imprint of the impending eruptions that transcends during the first eruption stages. Some possible reasons are outlined here. Then, the connection to the inner heliosphere with the aim of providing both a boundary condition and a baseline for inner-heliospheric propagation models is discussed, using magnetic helicity and its conservation principle as the cohesive material for connecting vastly different temporal and spatial scales. What high-energy solar forcing on Earth means for stellar systems of magnetically active hosts and relatively low-beta astrospheres is provided as a paradigm of solar-stellar connection and an outlook for future lines of research.
The seminar will be held in a hybrid mode, in person in building 200B, room 00.07 and transmitted online using the following permanent Blackboard Collaborate link, that can be used for all the upcoming seminars in this academic year:
https://eu.bbcollab.com/guest/6fc7259fc2ba4f29af721ccb6a19eefd
