Effects of Plasma Composition Variations on the Radiative Cooling of Solar Flare Loops

The plasma composition in the solar corona is variable, with a strong dependency on the first ionisation potential (FIP) of elements. In flaring regions, plasma composition has been shown to have significant spatial and temporal variations, likely driven by dynamical processes triggered by energy release at the reconnection site. The origin of these variations and their impact on flare loop dynamics are not yet fully understood. In this work, we use high cadence Hinode EIS spectroscopic observations of the M-class flare peaking at 13:56 UT on 2 April 2022, alongside simulations from the 0D EBTEL hydrodynamic model, to investigate the role of plasma composition in modulating radiative losses in solar flare loops. We identify two regions along the flare loop arcade, with distinct FIP bias values as well as cooling rates, suggesting that spatial variations in plasma composition may play a key role in influencing flare loop cooling. In this framework, I will also discuss the potential of high resolution spectropolarimetric observations from the upcoming IBIS 2.0 instrument, currently under installation at the THEMIS telescope, particularly for advancing studies of the physical mechanisms driving plasma composition variations, flare dynamics and the coupling between the two.