摘要
The plasmapause locations determined from the Chang'e-3(CE-3) Extreme Ultraviolet Camera(EUVC) images and the auroral boundaries determined from the Defense Meteorological Satellite Program(DMSP) Special Sensor Ultraviolet Spectrographic Imager(SSUSI) images are used to investigate the plasmaspheric evolutions during substorms. The most important finding is a nightside pointing plasmaspheric plume observed at 23:05 UT on 21 April 2014 under quiet solar wind and geomagnetic conditions, which drifted from the dusk sector. High correlations between the plasmapause evolutions and the auroral signatures exist during substorms. After substorm onset, the plasmapause erosion and the equatorward expansion of the auroral oval occur almost simultaneously in both MLT and UT, and then both the erosion and the expansion propagate westward and eastward. It is suggested that the plasmaspheric erosion and its MLT propagations are induced by the enhanced earthward plasma convection during substorm period, and the substorm dipolarization causes pitch-angle scattering of plasma sheet electrons and the resulting precipitation excites aurora emissions at the same time.
The plasmapause locations determined from the Chang’e-3 (CE-3) Extreme Ultraviolet Camera (EUVC) images and the auroralboundaries determined from the Defense Meteorological Satellite Program (DMSP) Special Sensor Ultraviolet Spectrographic Imager(SSUSI) images are used to investigate the plasmaspheric evolutions during substorms. The most important finding is a nightsidepointing plasmaspheric plume observed at 23:05 UT on 21 April 2014 under quiet solar wind and geomagnetic conditions, which driftedfrom the dusk sector. High correlations between the plasmapause evolutions and the auroral signatures exist during substorms. Aftersubstorm onset, the plasmapause erosion and the equatorward expansion of the auroral oval occur almost simultaneously in both MLTand UT, and then both the erosion and the expansion propagate westward and eastward. It is suggested that the plasmaspheric erosionand its MLT propagations are induced by the enhanced earthward plasma convection during substorm period, and the substormdipolarization causes pitch-angle scattering of plasma sheet electrons and the resulting precipitation excites aurora emissions at thesame time.
基金
supported by National Natural Science Foundation of China (41674155 and 41274147)
Youth Innovation Promotion Association of Chinese Academy of Sciences (No.2017258)
Key Research Project of Chinese Academy of Sciences:Application Research on the Scientific Data from Chang’E-3 Mission (KGZD-EW-603)