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The Dependence On Zenith Angle Of The Strength Of 3-Meter Equatorial Electrojet Irregularities, H. M. Ierkic, Bela G. Fejer, D. T. Farley
The Dependence On Zenith Angle Of The Strength Of 3-Meter Equatorial Electrojet Irregularities, H. M. Ierkic, Bela G. Fejer, D. T. Farley
Bela G. Fejer
Radar measurements in Peru were used to deduce the zenith angle dependence of the scattering cross section of plasma irregularities generated by instabilities in the equatorial electrojet. The irregularities probed by the 50 MHz Jicamarca radar had a wavelength of 3m. The cross section for the type 2 irregularities was isotropic in the plane perpendicular to the magnetic field, while the cross section for the stronger type 1 irregularities varied with zenith angle at a rate of approximately 0.3 dB/degree; the horizontally traveling waves were more than 100 times stronger than those traveling vertically.
Type I Radar Echoes From Theequatorial Electrojet With Double Peaked Doppler Spectra, Bela G. Fejer, D. T. Farley, P. Johnston, B. B. Balsley
Type I Radar Echoes From Theequatorial Electrojet With Double Peaked Doppler Spectra, Bela G. Fejer, D. T. Farley, P. Johnston, B. B. Balsley
Bela G. Fejer
Normal type 1 radar echoes obtained from relatively large zenith angles have a power spectrum with a single narrow peak whose Doppler shift corresponds approximately to the acoustic velocity in the medium. On some occasions, however, this single maximum splits into two distinct peaks, separated in phase velocity on one occasion by 270 m/s. This bifurcation is most easily observed at large zenith angles during daytime when a narrow antenna beam is used. It has also been seen in a daytime experiment in which radars at Jicamarca and Huancayo simultaneously probed the same region from two different radar zenith angles. …