Speaker
Description
First Name: Muriel Zoë
Last Name: Stiefel
Affiliation: FHNW & ETH Zürich
All Authors: Muriel Zoë Stiefel, Paolo Massa, Barbara Palumbo, Satoshi Masuda, Louise Harra, Säm Krucker
Abstract: Thanks to the unique orbit of Solar Orbiter, we can analyze X-class flares in hard X-rays (HXR) for the first time from different vantage points. By combining measurements from the Spectrometer/Telescope for Imaging X-rays (STIX) on Solar Orbiter, and the Hard X-ray Imager (HXI) on the Advanced Space-based Solar Observatory (ASO-S), we can study the hottest plasma in X-class flares, commonly referred to as the superhot component. Our analysis focuses on the X7 and X9 class flares that occurred on October 1st and 3rd, 2024. During this time, Solar Orbiter and Earth were separated by 90 degrees, allowing for unique observations from two very different perspectives. Our findings include a systematic shift between the hot and the superhot components, with the superhot component located higher above the flare ribbons. This supports the theory that the superhot HXR signal may be a signal of direct heating in the corona at the reconnection site. First thermal energy estimates suggest that the energy in the superhot component can account for up to 20% of the energy of the hot component, highlighting the significance of the superhot components in the overall flare energy budget.