Long wave part of the plasma turbulence spectrum in the lower E-region

In the lower polar E-region electric field and plasma density fluctuations were measured with rocket-borne instrumentation (a floating double probe system and a retarding potential analyzer) during the ROSE project. The observational data are presented and compared with the recently developed theory (Gurevich et al. 1996) for long wave ionospheric plasma oscillations induced by the neutral turbulence. The measured shape and anisotropy of the plasma turbulence spectra at ionospheric heights below about 95 km are well described by this theory. Significant amplification of the low frequency plasma fluctuations in strongly disturbed ionospheric conditions is established.