EISCAT/CRRES observations: Nightside ionospheric ion outflow and oxygen-rich substorm injections
UNSPECIFIED. (1996) EISCAT/CRRES observations: Nightside ionospheric ion outflow and oxygen-rich substorm injections. ANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES, 14 (10). pp. 1032-1043. ISSN 0992-7689Full text not available from this repository.
We present combined observations made near midnight by the EISCAT radar, all-sky cameras and the combined released and radiation efects satellite (CRRES) shortly before and during a substorm. In particular, we study a discrete, equatorward-drifting auroral are, seen several degrees poleward of the onset region. The are passes through the field-aligned beam of the EISCAT radar and is seen to be associated with a considerable upflow of ionospheric plasma. During the substorm, the CRRES satellite observed two major injections, 17 min apart, the second of which was dominated by O+ ions. We show that the observed are was in a suitable location in both latitude and MLT to have fed O+ ions into the second injection and that the upward flux of ions associated with it was sufficient to explain the observed injection. We interpret these data as showing that arcs in the nightside plasma-sheet boundary layer could be the source of O+ ions energised by a dipolarisation of the mid- and near-Earth tail, as opposed to ions ejected from the dayside ionosphere in the cleft ion fountain.
|Item Type:||Journal Article|
|Subjects:||Q Science > QB Astronomy
Q Science > QE Geology
Q Science > QC Physics
|Journal or Publication Title:||ANNALES GEOPHYSICAE-ATMOSPHERES HYDROSPHERES AND SPACE SCIENCES|
|Official Date:||October 1996|
|Number of Pages:||12|
|Page Range:||pp. 1032-1043|
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