We report on the analysis of Io-C sources observed at Nancay observatory (France). The study of Io-C morphology, from the dynamic spectra, allows us to show the recurrence of fine emission features in the same region of the CML-Io diagram. Thus the component, with right-hand polarization, has a constant spectrum, one large vertex-late arc reaching frequencies of about 30MHz. Simultaneously, the structures with left-hand polarization, observed at frequencies less than 25 MHz, present two samples: splitting and vertex-late arcs. We find a temporal correlation between the right-hand and left-hand polarization structures, where the splitting seems to be the precursor of the rest of the emission. The analysis of Io-C dynamic spectra is completed by the measurements of the Stokes polarization parameters. In this case we show that the polarization for a given event is the same for the splitting and vertex-late arcs, where both have left-hand polarizations. To interpret our results we compare our spectral observations to the Goldstein-Thieman model. We show correspondence between model and observation concerning the arc structures. But there is no correspondence when we take in consideration both polarizations and we try to explain the common spectral and temporal features. This correlation between both components seems to be more evident if they are associated to one and the same emission cone located in one hemisphere.
Astronomy and Astrophysics
- Pub Date:
- November 1995
- PLANETS: JUPITER;
- RADIO CONTINUUM: SOLAR SYSTEM