The Structure of the Electron Diffusion Region in Asymmetric Magnetic Reconnection

Abstract:

Despite a multitude of research efforts in recent history, theoretical and modeling predictions of the structure of the reconnection diffusion region continue to uncover a multitude of surprises. A common theme among most predictions is a complex structure, with prominent spatial gradients, which determine the variation of magnetic fields, currents, and structures of distribution functions. On the electron scales, there is growing consensus that these scales are given either by the electron bounce width or by local electron Larmor radii, but many unsolved puzzles remain, particularly in asymmetric configurations, like those investigated by NASA’s Magnetospheric Multiscale mission during the first part of its scientific mission. In this presentation, we will present an overview of recent results pertaining to the electron physics of asymmetric magnetic reconnection. We will describe both general features, likely to be encountered in any asymmetric system, as well as features, which depend on key parameters such as magnetic shear angle and temperature and density asymmetries. Ww will compare these predictions to MMS observations of magnetopause reconnection.