MPS Seminar: White Light Solar Flares (Säm Krucker)

Solar flares were discovered by Carrington (1859) and Hodgson (1859) through their white-light emissions. Although the emission mechanism of white-light flares is still not understood today, we now know that such radiation is produced at the footpoints of flaring magnetic loops. Compared to the pre-flare variability of the Sun in the optical range, white light flares only locally enhance the emission. White light flare sources therefore are clearest seen in large flares but could be possibly present in all flares. Joint observations in the optical, X-ray, and gamma-ray range reveal that the white light flare emission process is somehow linked to the energy deposition of flare-accelerated electrons and ions as they interact and heat the lower layers of the solar atmosphere. In this talk, I will give first an introduction to white light solar flares and then show new results obtained by the hard X-ray telescope STIX onboard Solar Orbiter and AIA/HMI.