Kinetic‐Size Magnetic Holes in the Terrestrial Foreshock Region

Abstract

AbstractKinetic‐size magnetic holes (KSMHs) can accelerate and heat the particles, resulting the energy dissipation in space plasmas. KSMHs in the terrestrial foreshock region are statistically investigated based on the Magnetospheric Multiscale data from October 2015 to December 2019. A total of 98 KSMHs are successfully selected, and most of them are accompanied by electron vortices. The fluxes of electrons at ∼90° of pitch angle enhance inside the magnetic holes, where the perpendicular and total electron temperature increase, and the parallel electron temperature slightly decreases inside these magnetic holes. Moreover, we reveal a novel phenomenon that a lot of the observed KSMHs are probably moving toward the Sun in the plasma flow frame. Such sunward propagating KSMHs are detected for the first time in the foreshock region. We propose that these observed KSMHs are probably generated in the foreshock region and then propagate to the Sun.