FURTHER INVESTIGATIONS OF STORM-TIME SUB ELF EMISSIONS
Abstract
This report is concerned with the following properties of certain types of sub ELF emissions (delta f = 0.2-5 cps) observed during magnetic storms: (1) The aural characteristics of the emissions obtained from time- compressed magnetic tape; (2) the frequency-time (f-t) characteristics of the emissions as displayed on sonagrams; (3) the degree of simultaniety of emissions observed simultaneously at widely separated locations (the four Lockheed Pacific Ocean Stations); and (4) the relationships between the occurrence times of the emissions and the following quantities: (a) Magnetic Kp index, (b) local time of day, and (c) local sunset. Perhaps the most interesting result of the investigation is the observation that storm-time sub ELF emissions seem to excite natural resonances in the exosphere. This effect is explained in terms of an existing theoretical model. Also of interest is the observation that the signals are most frequently observed near 800 PM local time. The occurrence time seems to indicate that the signal source is asymmetric with respect to the sun-earth line.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 25, 1964
- Accession Number
- AD0623993
Entities
People
- K. D. Amundsen
- Lee Tepley
- R. C. Wentworth
Organizations
- Lockheed Martin Missiles and Space