Abstract. In late March and early April of 1995, an experimental campaign involving the modification of the F2 ionospheric layer took place in Russia and Ukraine. HF pulsed and CW Doppler radar observations of field-aligned irregularities within the region over the Sura heater were made with the UTR-2 radio telescope serving as the receiver. In this paper, some preliminary results of our bistatic radar observations of the modified region are presented. These results include measurements of the drift, evolution, and decay of inhomogeneities and turbulence contained within the modified region and evidence of interactions between the ionospheric plasma, Alfv•n waves, and free geomagnetic pulsations.
Bistatic HF radar scatter from magnetic field‐aligned irregularities created by the Sura heater near Nizhny Novgorod, Russia, has been detected and analyzed at the UTR 2 decametric radio telescope near Kharkov, Ukraine. The decay phase of the irregularities exhibits two decay time constants in general. The shorter time constant, which is only sometimes seen, is consistent with classical diffusive dissipation theory for small‐scale, field‐aligned waves. The longer time constant, which is almost always present, is much too long to be accounted for by diffusion. It is more likely associated with the decay of large‐ and intermediate‐scale plasma turbulence. Three‐wave nonlinear interaction with turbulent modes is shown to be capable of generating the field‐aligned irregularities.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.