An Investigation of Perpendicular Gradients of Parallel Electric Field in Separatrix Regions in Using the Magnetosphere Multiscale Mission

Particle heating and acceleration observed throughout the Earth's magnetosphere has been associated with magnetic reconnection events. Analytic studies have demonstrated that a curl of the parallel electric field is necessary for magnetic reconnection to occur. The curl of the parallel electric field has been examined in numerical simulations. We focus on the dynamics in the separatrix region. The Magnetosphere Multiscale Mission, a constellation of four satellites flown in a tight tetrahedral formation, has made multi-point high quality 3D electric field measurements in the Earth's dusk sectors, allowing for the first direct measurements of the curl of the parallel electric field. We aim to present a preliminary survey of parallel electric fields as measured by MMS and discuss the implications on magnetic reconnection and future observations of magnetic reconnection.