VARIATIONS OF THERMAL ELECTRON-ENERGY DISTRIBUTION ASSOCIATED WITH FIELD-ALIGNED CURRENTS

Relationships between thermal electrons and field aligned currents (FACs) in the auroral region have been investigated using data simultaneously obtained from the Thermal Electron Detector (TED) and the fluxgate magnetometer both onboard the EXOS-D satellite. Several features resulted from the observations are summarized as; (1) At altitudes from 300 to 1800km, electron temperature in the upward FAC region is higher than that of the neighboring no FAC region by the increment DELTA-T=1100 approximately 9500K, while the temperature is lower in the downward FAC region by the decrement -DELTA-T=500 approximately 1500K. (2) the electron temperature increase in the upward-current region grows with an increase of the FAC density. (3) The thermal electrons do not have Maxwell distribution in the upward-current region at altitudes higher than about 2000km.