Speaker
Description
First Name: Ioannis
Last Name: Kontogiannis
Affiliation: ETH Zurich
All Authors: I. Kontogiannis, L. Harra, S. Berdyugina, Y. Zhu, K. Barczynski, M.Z. Stiefel, H. Collier, J. McKevitt, S. Castellanos Duran
Abstract: In 2024 Solar Orbiter monitored a significant portion of the Sun's far side, enabling near-continuous, long-term monitoring of the extremely complex region NOAA 13664, from emergence to decay. We combined line-of-sight magnetograms from SO/PHI and SDO/HMI as well as EUV coronal imaging from SO/EUI and SDO/AIA, along with flare detections from STIX and GOES, to create a 94-day long, near-continuous data set. Repeated flux emergence events formed an extremely complex configuration, which reached its peak size within roughly one month. A prolonged, gradual decay phase followed, which lasted about six weeks, after which a more rapid decay ensued. The flaring activity remained elevated for almost three rotations and it was exceptionally intense near the peak phase, with multiple X-class flares culminating in an X16.5 event. We derived time series of four magnetic non-potentiality parameters, the longest ones for a single active region to date. These time series were consistent, despite originating from two different instruments, capturing the region’s full evolution and showing strong correlation with the flare index. Our results highlight the critical role of long-term, multi-vantage-point observations in understanding active region evolution and eruptivity. An exploration of the long-term evolution of the coronal properties through EUV spectroscopy from Hinode/EIS is underway.