Quantifying CME effects on plasma parameters and elemental abundance recovery during a flare event with X-ray spectroscopy

The connection between coronal mass ejections (CMEs) and solar flares has been studied statistically, but the details of this relationship remain largely unknown. Soft X-rays provide us a unique depiction of eruption dynamics due to the coronal first ionization potential (FIP) bias: abundances of low FIP elements are observed to peak at flare onset, and decrease abruptly towards photospheric values during the impulsive phase before recovery. Recovery times have been linked to the time when the plasma is trapped within the magnetic field, suggesting that CMEs delay abundance recovery. This provides a useful tool for studying the characteristics and dynamics of flares and CMEs and their effects on each other.

This study aims to connect flare characteristics to CME properties using soft X-ray spectroscopy and hard X-ray imaging. The temporal evolution of plasma parameters and elemental abundances during the eruption event are analyzed with soft X-ray data from the SUNSTORM 1 X-ray Flux Monitor for CubeSats (XFM-CS). Evolution of the X-ray loop emission source is investigated with a time-series analysis of image reconstructions utilizing The Spectrometer Telescope for Imaging X-rays (STIX) instrument on board Solar Orbiter. CME kinematics are analyzed with a variety of remote-sensing data. The resulting study shows that emission from a post-CME looptop source significantly affects eruption dynamics by slowing down abundance recovery, and relates this evolution to the flare profile.