Structure and evolution of dayside magnetopause reconnection exhaust

Magnetic reconnection at Earth's dayside magnetopause heats and accelerates plasma with energy liberated from the field reconfiguration. This so-called reconnection exhaust can be observed several R_E away from where reconnection is taking place, and in some cases it is possible to determine reconnection quantities such as the location and reconnection rate from exhaust properties. As direct observations of reconnection regions are difficult, due to their small size and high variability, such remote techniques are key to understanding large-scale magnetopause structure and dynamics.

We employ exhaust observations by NASA's Magnetospheric Multiscale (MMS) mission to determine the location of reconnection sites, the evolution of exhaust features such as D-shaped distributions, and influences on reconnection jet velocities. We find that exhaust D-shaped distributions should remain discernible at significant field-aligned distances from the reconnection site, and we infer magnetopause dynamics between reconnection and exhaust observation by comparing exhaust properties at varying field-aligned distances.