Whistler leakage from narrow ducts
Abstract
Low altitude satellite observations of a variation in the upper cut-off-frequency of whistlers with latitude (at constant altitude) can be convincingly explained in terms of different whistler frequencies leaving a duct at different altitudes. This selective leakage is explained by a downcoming wave escaping from a duct at an altitude where its wavelength becomes approximately equal to the duct width. This altitude is shown to decrease with increasing wave frequency. Leakage according to this mechanism is shown to result in a minimum duct width at a given altitude for ducted guidance of VLF waves. It is found to be consistent with the distribution of duct widths inferred from whistler observations made aboard the low altitude satellite ISIS 1.
- Publication:
-
Journal of Atmospheric and Terrestrial Physics
- Pub Date:
- May 1986
- DOI:
- 10.1016/0021-9169(86)90122-4
- Bibcode:
- 1986JATP...48..455S
- Keywords:
-
- Ducts;
- Satellite Observation;
- Wave Propagation;
- Whistlers;
- Altitude;
- Isis Satellites;
- Leakage;
- Very Low Frequencies;
- Wavelengths