Low-frequency electric field fluctuations and field-aligned electron beams around the edge of an auroral acceleration region
نویسندگان
چکیده
Electron beams narrowly collimated to the magnetic field line were observed continuously from a downward current region to an auroral acceleration region (i.e., upward current region). They were well correlated with lowfrequency electric field fluctuations in the auroral acceleration region as well as in the adjacent downward current region. Magnetic field fluctuations were found only in the downward current region. The analysis suggests that static field-aligned electric fields are not fully responsible for the filed-aligned electron acceleration; the ac electric field, presumably associated with Alfvenic fluctuations, should also be involved in the acceleration of ionospheric electrons.
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