SUBSTORM LOW-ENERGY PARTICLE DECREASE NEAR THE INNER EDGE OF THE PLASMA SHEET

The injections of energetic particles and dipolarization of the magnetic field are well-known sig- natures of magnetospheric substorm in the near-Earth region of the plasma sheet. However, the variations of low-energy particles in these phenomena are not suffi- ciently examined. Here we consider the behavior of the low-energy (30 eV - 28.5 keV) particles near the Earthward edge of the plasma sheet as observed by the CRRES satellite during four substorms and their contri- bution in the total pressure changes. We found that the low-energy ion pressure and total (plasma and magnetic field) pressure at r~6 RE decrease during the local dipolarization. However after a large scale dipolariza- tion, the total pressure increases during the events when the CRRES was located near the equatorial plane.