论文信息 - Small scale auroral absorption events associated with substorms

Small scale auroral absorption events associated with substorms

WE describe the first results obtained from a new facility designed to study auroral absorption events exhibiting small scale spatial structure and rapid temporal variations. The absorption is measured by means of a modern solid-state riometer with high time resolution1 and the spatial resolution is obtained using a narrow-beam antenna with 64 elements. The most striking observations made so far involve intense, short-lived ‘spikes’ of absorption associated with the onsets of auroral substorms. These spikes, which seem to be of small spatial scale, are probably related to the sudden ionospheric absorption (SIA or SAI) events reported by previous workers2–5 and perhaps to the ‘spikes’ of intense energetic electron precipitation observed from polar-orbiting satellites6–11. Five such spikes were observed during November and December 1975.

W. I. Axford | E. Nielsen | E. NIELSEN | W. I. AXFORD

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