Coordinated ATS 5 electron flux and simultaneous auroral observations

Journal Article · Thu Jan 01 04:00:00 EST 1976 · J. Geophys. Res., v. 81, no. 1, pp. 97-110

DOI:https://doi.org/10.1029/JA081i001p00097· OSTI ID:4002814

Mende, S B; Shelley, E G

All-sky camera (ASCA) observations were made at the field line conjugate of the ATS 5 satellite. The field of view of these cameras covered the region of the magnetosphere from L=5 to L=11 at the approximate longitude of the ATS field line conjugate. With this coverage, definite statements can be made concerning the correlation of the auroras observed by the ASCA's and the magnetospheric trapped fluxes. In general, auroral forms are not simply correlated with the synchronous altitude electron fluxes. The presence of hot plasma at the ATS 5 satellite is a necessary but not sufficient condition for the occurrence of local auroras. On quiet days the hot plasma does not penetrate into the magnetosphere far enough to reach the ATS 5 orbit. Under these conditions, no auroras are observed at the field line conjugate, but auroras are usually observed on higher- latitude field lines. On more disturbed days, auroral arcs are observed at lower latitudes when the plasma sheet penetrates into the ATS 5 orbit. There is no general correlation between the intensity of the trapped electron fluxes observed by ATS 5 and the intensity of auroras observed by the ASCA's. Auroral displays exhibit very fast fluctuations, whereas the ATS 5 electron fluxes change on a much slower time scale. However, significant qualitative correlation between the ASCA data and the trapped fluxes is observed when a local plasma injection event occurs near ATS 5. The clearest signature of the injection event is magnetic and is most pronounced as a recovery of a negative bay in the north-south component of the field at the ATS 5. The local injection generally produces structured auroras such as breakup events and sometimes westward-traveling surges. A significant correlation is observed with the intensification of a diffuse uniform glow accompanying the structured auroral activity. (AIP)

• Research Organization: Lockheed Palo Alto Research Laboratory, Palo Alto, California 94304
• Sponsoring Organization: USDOE
• NSA Number: NSA-33-027119
• OSTI ID: 4002814
• Journal Information: J. Geophys. Res., v. 81, no. 1, pp. 97-110, Journal Name: J. Geophys. Res., v. 81, no. 1, pp. 97-110; ISSN JGREA
• Country of Publication: United States
• Language: English

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