Electron Aurora and Polar Rain Dependencies on Solar Wind Parameters

Abstract

Data analysis was performed using 17 years of DMSP SSJ/4/5 data to characterize the relations between the solar wind parameters and the electron low‐energy fluxes measured on both magnetic poles (magnetic latitude above 55°). Inputs are solar wind velocity, density, dynamic pressure and Bz of the interplanetary magnetic field. Median of electron energy flux for each MLAT‐MLT pair have been computed for given values of solar wind condition parameters. Results highlight that high velocity, density or pressure implies higher energy flux overall, higher polar rain energy fluxes, and wider nightside oval. There seems to be a positive correlation between polar rain and solar wind density, contrary to a previous study. As a function of Bz, the oval width has a “U” shape and the polar cap activity a “V” shape, with their minimum at Bz around zero.

Complex dayside particle precipitation observed during the passage of a solar wind rotational discontinuity

“…There have been many studies of the solar wind control of the dayside particle precipitation at high-latitudes, either in the open-field line regions such as cusp, mantle, low-latitude boundary layer (LLBL), open-field line LLBL (open-LLBL), and high-latitude boundary layer (Yeager et al, 1976;Newell and Meng, 1992;Lockwood et al, 1993;Lyons et al, 1994;Wing et al, 1996;Wing et al, 2001;Fairfield et al, 2008;Shi et al, 2013;Shi et al, 2009;Newell et al, 2009;Shen et al, 2022;Bouriat et al, 2023) or in the closed field lines such as boundary plasma sheet and central plasma sheet (Newell and Meng, 1992;Newell et al, 2004;Bouriat et al, 2023). However, there have been fewer studies on the response of the high-latitude particle precipitation to solar wind DDs, either RDs or TDs.…”