In-Situ Measurementes of Wave Electric Firelds in the Equatorial Electrojet

R. F. Pfaff
M. C. Kelley
B. G. Fejer
N. C. Maynard
K. D. Baker


Electric field wave measurements have been performed on two sounding rockets in the equatorial ionosphere. During a daytime flight from Chilca, Peru, intense elecrostatic waves were detected on the upward directec electron density gradient. Duing a nighttime flight from Kwajalein Atoll, similar waves were detected on a downward directed gradien. These results are in agreement with a gradient drift instability explanation of the generation of the waves. The wave amplitudes were as high as 5 mV/m implying pertubation drifts comparable to the driving drift velocities. Power spectra from the turbulent region show a peak at long wavelengths, followed by a nearly flat spectral region before breaking into a power law form with hegative index of 3.6-3.7 for λ