Abstract
Akebono (Exos D) observations demonstrate that polar cap arcs sometimes have a fine structure, that is, multiple (double or triple) arcs with spacing of a few tens of kilometers. The multiple polar cap arcs are dominantly observed in the nightside polar cap region, suggesting that low background conductance favors the appearance of the structured arcs. A relationship between the spacing and the average energy of the precipitating electrons is investigated. Results show that a higher energy leads to a wider spacing. Akebono observations also show the existence of a downward current region embedded between upward current regions (arcs). Comparison of the observations with results from a coupled magnetosphere-ionosphere Sun-aligned arc model is made, which shows good qualitative agreement between the modeling and observational results on the spacing-energy dependence and the effect of background ionospheric conductance.
| Original language | English |
|---|---|
| Pages (from-to) | 645-653 |
| Number of pages | 9 |
| Journal | Radio Science |
| Volume | 31 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 1996 |
| Externally published | Yes |
ASJC Scopus subject areas
- Condensed Matter Physics
- Earth and Planetary Sciences(all)
- Electrical and Electronic Engineering