Russian SHAREABLE DATA CENTER East Siberian Center for the Earth's Ionosphere Research (SDC ESCEIR) Institute of Solar-Terrestial Physics SB RAS Upper Atmosphere Physics and Radiowave Propagation Department

Capabilities and samples
Incoherent scatter ionosphere diagnostics subdivision

Anomal high power signal registration (coherent echo) during the 15 July 2000 ionospheric storm

One of the rarest but most interesting effects which can be observed with the Irkutsk IS radar is anomal high power signal registraion(coherent echo) due to strong magnetic storms. These signals (often called radioaurora) come from the side lobes of the antenna beam. These signals are formed at E-layer heights in the presence of a strong electric field which causes particles to drift. Due to the difference in electron and ion fluxes for the particle drift we have plasma current two-stream instabilities which caused strong irregularities in electron density along magnetic field lines.To register these signals we need that the antenna beam is perpendicular to the magnetic field, that is, the reflectrion power has a strong aspect sencitivity. For the Irkutsk IS radar these conditions are satisfied in a sufficient larch region 400-1100 km to the north from Irkutsk. From the figure we can see that reflection dymanics differs sufficiently for various storm phases.