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Radda, G. J.

Publications and source records attributed to Radda, G. J..

3 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Regular radiation field pulses produced by intracloud lightning discharges

Sequences or bursts of uniform pulses have been recorded during a large fraction of intracloud lightning discharges in Florida and Arizona. The wave form of a typical pulse begins with a fast large-amplitude portion followed by a small and slowly varying overshoot. The full width and half maximum of the large amplitude peak is typically 0.75 microsec, and the time intervals between pulses are typically 5 microsec in both maritime and continental storms. The pulse shapes and interval times suggest that the source of these pulses in an intracloud dart-stepped leader process similar to that which has been photographed in discharges to ground.

Krider, E. P.↗
NASA NTRS1975

Radiation field wave forms produced by lightning stepped leaders

Broadband electric field data are presented which show stepped leader wave forms preceding records of distant lightning return strokes. The majority of leader pulses are characterized by a large initial peak with a small and slow opposite overshoot. Total pulse durations range from 15-40 microsec several milliseconds before the return stroke to 2-10 microsec immediately preceding the return stroke. Close to the ground the stepped leader pulses occur at regular 10- to 20-microsec intervals and are almost unipolar with rise times of about 1 microsec and full widths at half maximum in the range from 1 to 3 microsec. The ratio of the peak of the last leader pulse to the subsequent return stroke peak is typically 0.1, which suggests a peak step current near the ground of about 10% of the return stroke peak current.

Krider, E. P.↗