Dynamic spectra of S-bursts of Jovian decametric radiations are obtained by using a high time resolution radio spectrograph which has a time resolution of 2 msec and the bandwidth of 2 MHz. Within occurrence of 65 S-burst events observed in the period from 1983 to 1999, 26 events have been identified as the S-N burst events, which are characterized by the interaction between the S-burst emissions and the Narrow band emissions. In the dynamic spectra of the S-N burst, the trend of emissions with negative and slower frequency drift named as "Trailing Edge Emission" are often observed shortly after the appearance of the S-burst. Detailed analyses of these phenomena revealed that the Trailing Edge Emission is not a manifestation of S-burst with slower drift rate but a variation of N-burst. The results suggested that S-burst and the associated Trailing Edge Emission are formed simultaneously started from a common region with different drift rates. It has been further suggested that the appearance of the S-bursts is not controlled by the geometrical effect between the source region and the observer, but directly reflects the generation of the source region widely distributed in an altitude range from a few thousands km to 30,000 km, along the Io flux tube.
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science