Accession Number : AD0718384

Title :   Whistlers with Harmonic Bands Caused by Multiple Stroke Lightning.

Descriptive Note : Progress rept.,

Corporate Author : IOWA UNIV IOWA CITY DEPT OF PHYSICS AND ASTRONOMY

Personal Author(s) : Shaw,Robert R. ; Gurnett,Donald A.

Report Date : DEC 1970

Pagination or Media Count : 19

Abstract : Whistlers received with the Injun 5 satellite are frequently observed to have bands with decreased signal amplitude at equally spaced frequency intervals. The frequency spacing between the bands is typically about 10 to 30 Hz. As many as 30 such bands have been observed on a single whistler. Subsequent investigations have shown that the bands are instead due to double or multiple strokes in the initial lightning discharge which result in destructive interference of the whistler signal at equally spaced frequency intervals. The frequency spacing between the interference bands is given by the inverse of the time interval between the lightning strokes. This simple explanation for these bands accounts for a number of peculiar characteristics which could not be accounted for with the gyrofrequency harmonic interaction hypothesis.

Descriptors :   (*WHISTLERS, HARMONIC ANALYSIS), ATMOSPHERIC SOUNDING, LIGHTNING, FOURIER ANALYSIS, WAVE PROPAGATION, SCIENTIFIC SATELLITES

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE