An interferometric study of Jupiter's decimeter radio emission

NOTE: Text or symbols not rederable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. An interferometric study of the decimeter radio emission from the planet Jupiter has recently been carried out at the Owens Valley Radio Observatory. Using the two 90-foot paraboloids as an interference polarimeter, observations have been made with various eastwest spacings ranging from 300 to [.......] at 10.4 cm. and 300 to [......] at 21.2 cm. and also with some critical north-south spacings at 10.4 cm. The visibility functions obtained are consistent with earlier measurements, which gave the polar and equatorial dimensions as one and three planetary diameters respectively, but they are more complete and extend to larger baselines. They permit the fitting of a rather detailed model for the decimeter brightness distribution. The observations are consistent with a symmetrical synchrotron emission source having the polarization properties one would expect with a dipole magnetic field. It probably is centered quite closely on the planetary disk, which is itself seen as a thermal radio source. The observations also indicate the presence of a small circularly polarized component in the radiation which varies in magnitude and sense as Jupiter rotates. Another result is that the disk emission at 10.4 cm. is about twice the thermal emission one would expect for a temperature of 130 [degrees] K. The implications of the various results are discussed