@article{oai:nipr.repo.nii.ac.jp:00001263, author = {Mukai, Toshifumi and Hirao, Kunio}, journal = {Memoirs of National Institute of Polar Research. Special issue}, month = {Sep}, note = {P(論文), Measurements of both upward and downward electron fluxes on the KYOKKO satellite have revealed following characteristics of the inverted-V events. (1) Inverted-V events have various durations from a few tens of seconds up to several minutes. Existence of the long-duration structure with nearly constant energy of the monoenergetic peak indicates that the inverted-V structure is stable rather than transient and also that the equipotential contours of the electric field for acceleration of auroral electrons are extensive in longitude and have a meridional cross-section that is V-shaped. (2) The source region of inverted-V electrons seems to be on the closed field lines as well as on the open field lines. (3) Inverted-V events occur at all local times except around noon and at higher latitudes in the dayside hemisphere, although the occurrence frequency is least in the morning sector (0300-1200MLT). They occur most frequently at invariant latitudes of 65°-70° in the premidnight sector under disturbed conditions.}, pages = {116--124}, title = {Characteristics of the inverted-V events observed by the KYOKKO satellite}, volume = {22}, year = {1982} }