Dual-frequency interplanetary scintillation observations of the solar wind

The results of observations of interplanetary scintillation (IPS) using the telescopes of EISCAT, in northern Scandinavia, and the ESR, on the Svalbard archipelago in the high Arctic, observing at frequencies of 1420 MHz, 928 MHz and 500 MHz are presented. Significant correlation is seen at time lags of 1.5–2 s when the observing frequencies of each telescope differ by a factor of almost three. Simple plane of sky solar wind speeds are also estimated and found to be consistent between single- and dual-frequency correlations.