CORRELATION BETWEEN TERRESTRIAL MYRIAMETRIC AND KILOMETRIC RADIO-BURSTS OBSERVED WITH GALILEO

Data from the Galileo plasma wave system recorded during an investigat ion of the Earth magnetotail on December 8, 1990, are analyzed in both the myriametric and the kilometric wavelength range. In the far tail, between 80 and 30 Earth radii, two components are observed in the myr iametric range (frequencies between 6 and about 30 kHz): (1) the ''cla ssical'' trapped continuum radiation with a smoothly varying intensity in time and (2), superposed on this component, bursts of waves with t ypical spectral densities of 10(-15) V(2)m(-2)Hz(-1). These bursts of myriametric waves are shown B to correlate with bursts of intense auro ral kilometric radiation (AKR) with typical spectral density of 10(-12 ) V(2)m(-2)Hz(-1). This bursty myriametric radiation is the analog of the low frequency radiation (LFR) reported by Filbert and Kellog; (198 9). Its close correlation with the kilometric radiation suggests the e xistence of a direct relationship between these two radiations. A gene ration mechanism that explains this correlation and the frequency gap between the AKR and the LFR is proposed.