Energetic electron interaction with magnetic islands in Earth's magnetosphere

Here we investigate the interaction between magnetic islands and plasma electrons from lab to space through comparison of data from NASA's Magnetospheric Multiscale (MMS) mission and experiments at the DIII-D tokamak. To analyze MMS data, we developed a semi-automated Python workflow that streamlines event selection based on bipolar signatures in the magnetic field, coordinate transformation, and diagnostic plotting to detect magnetic islands. We then incorporated data from the Fast Plasma Investigation (FPI) instrument to analyze electron densities and energies for magnetotail surfaces with magnetic island signatures. It was found that background plasma electron densities peak near island O-points, while bursts of energetic electrons were detected near island X-points. These findings mirror the behavior found in DIII-D magnetic islands, demonstrating that magnetic islands in magnetized plasma affect local electron densities and the observation of energetic electrons in both lab and space environments. Although the focus of this study is on observations of quasi-static islands, we also consider how changes in magnetic island dynamics affect the resulting distribution of electron energies observed in both measurements. This study can further our understanding of cross-field transport processes relevant to both space weather prediction and fusion energy.