An automated approach to link solar flares and energetic particle events based on measurements from Solar Orbiter and modelled magnetic connectivity

Solar flares and associated eruptions are a known source of solar energetic particles (SEPs). Yet, it is often challenging to establish a precise link between individual flares and SEP events measured in-situ throughout the heliosphere. The Solar Orbiter mission with its Spectrometer/Telescope for Imaging X-rays (STIX ) and Energetic Particle Detector (EPD) provide new measurements for a systematic investigation of these phenomena. Based on these data, we developed an algorithm that automatically links solar flares to SEP events using a STIX flare list, model prediction of magnetic connectivity between the Sun and the spacecraft, and SEP electron measurements from EPD. A first evaluation shows that 50% of the links produced by the algorithm are actual physical links, while inversely 26% of all manually identified physical links were detected by the algorithm for the two-years test period in 2021 and 2022. This can be considered as a modest success rate for a fully automatic linkage between solar and in-situ events, but it provides a very helpful pre-selection of about 100 SEP-related flares compared to more than 5000 flares detected with STIX.