BROAD-BAND ELECTRONS OBSERVED BY THE DMSP SATELLITES DURING STORM-TIME SUBSTORMS

Electrons that have intense broadband spectra, are found to precipitat e in the equatorward part of the auroral oval. The electrons are obser ved by the DMSP satellites in association with particular substorms du ring the main phase of magnetic storms. Electron fluxes are drasticall y enhanced after the substorm onset at all the energies measured (32 e V to 30 keV) at magnetic latitudes lower than 60 degrees (L < 4). The energy flux of the electrons exceeds 1.0 x 10(13) eV cm(-2) s(-1) sr(- 1). The intense electron precipitation lasts less than 1 h. These char acteristics are significantly different from those seen in the central plasma sheet region. We suggest that an unknown energization mechanis m of these electrons exists at the inner part of the plasma. sheet at L < 4 during these particular storm-time substorms.