Universal Scaling of Thin Current Sheets

Abstract

AbstractThin current sheets (TCSs) with thicknesses about ion Larmor radii are widespread in space. It is important to describe their equilibrium structure allowing them to store and then explosively release the accumulated free energy. When ions are moving along quasi‐adiabatic trajectories while magnetized electrons follow guiding center drift orbits, TCSs can be described within the framework of a hybrid approach. The thickness of the embedded electron sheet remains uncertain because of the scale‐free character of electron motion. In this work, we propose a novel analytical model of the multilayer TCS that provides a universal expression describing the inner (embedded) electron sheet in dependence of TCS characteristics. An unusual property of the embedded electron layer revealed in this analysis is the nonlinear profile of the magnetic field in the inner layer: B(z) ~ z1/3, which conforms excellently with MAVEN observations of 43 TCSs in the Martian magnetotail.