Title: The spatial relationship of field-aligned currents and auroral electrojets to the distribution of nightside auroras
Abstract: Journal of Geophysical Research (1896-1977)Volume 82, Issue 35 p. 5589-5608 The spatial relationship of field-aligned currents and auroral electrojets to the distribution of nightside auroras Y. Kamide, Y. KamideSearch for more papers by this authorG. Rostoker, G. RostokerSearch for more papers by this author Y. Kamide, Y. KamideSearch for more papers by this authorG. Rostoker, G. RostokerSearch for more papers by this author First published: 1 December 1977 https://doi.org/10.1029/JA082i035p05589Citations: 83AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract In this paper, nearly simultaneous sets of ground-based magnetometer data, magnetic perturbations recorded at 800-km altitude by the polar-orbiting Triad satellite and auroral imagery and information on precipitating electrons in the energy range 200 eV < E < 20 keV obtained from the DMSP satellites are analyzed for intervals of moderate magnetospheric activity during which substorms were in progress. It is found that the boundaries of intense (>2 kR at 5577 Å) auroral features coincide with the boundaries of field-aligned current regions defined by the Triad data. In the morning sector the downward field-aligned current flows in the poleward portion of the auroral oval, and the intensity of this current appears not to be a function of the intensity of the related auroral features. These results suggest that the current is carried by upgoing thermal electrons from the ionosphere. On the equatorward side of the oval the region of the upward field-aligned current coincides with the bright aurora regime and is probably carried by precipitating energetic electrons. In the evening sector, regions of intense upward field-aligned currents are found to coincide with discrete auroral arcs and fluxes of precipitating electrons with energies peaked at several keV in the region immediately poleward of the eastward electrojet. This region is thought to coincide with the extension of the westward electrojet from the morning sector, and precipitating electrons in the bright auroral forms are thought to carry the upward field-aligned current in this region. In a narrow latitudinal area poleward of the upward current where no auroral luminosity is detected, downward field-aligned current is often observed, indicating the importance of ionospheric thermal electrons carrying the downward current. This current is thought to be connected to the equatorward Pedersen current of the equatorward electric field that is dominant in the westward electrojet region. In the equatorward half of the evening auroral oval the diffuse aurora is located in the region of the downward field-aligned current and, in general, collocated with the eastward electrojet. Citing Literature Volume82, Issue35Space Physics1 December 1977Pages 5589-5608 RelatedInformation
Publication Year: 1977
Publication Date: 1977-12-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
Cited By Count: 100
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot