Hot electrons as tracers of large-scale structure of magnetotail current sheets



[1] This paper is devoted to the investigation of the vertical electron temperature distribution in thin currents sheets of the Earth magnetotail. The dependence of electron temperature on magnetic field Te(Bx) is examined for 62 thin currents sheet crossings by the Cluster spacecraft. The profiles Te(Bx) are approximated by the simple expression TeTemax(1 − α(Bx/Bext)2), where α is a constant parameter, Temax is the maximum value of electron temperature and Bext is the amplitude of Bx obtained from the vertical pressure balance. The mean value of the parameter 〈α〉 ≈ 1. The profiles Te(Bx) are described in the frame of the theory of adiabatic electron heating in the course of the Earthward plasma convection. The comparison between the observed values of α and the theoretical predictions allows to estimate the scale Lx of observed current sheets along the magnetotail (Bz ∼ (−x/Lx)h) and the ratio of Lx and current sheet thickness Lz. For the majority of the observed thin current sheets Lx ∈ [5RE, 20RE] and the average ratio of the scales 〈Lx/Lz〉 ≈ 25.