During the Voyager 1 flyby of Saturn's moon Titan, the plasma wave instrument detected several types of plasma wave emissions. On the inbound leg a broad region of intense low-frequency noise was detected on the side of Titan facing away from Saturn. This noise has characteristics similar to the electric field turbulence observed in the magnetosheath at the earth and the ionosheath at Venus and is believed to be generated by newly created ions that are being accelerated in the vicinity of Titan by the corotational electric field. During the pass through the induced magnetic tail of Titan, a series of upper hybrid resonance emissions were observed. The electron density profile inferred from these emissions shows three distinct peaks with density of ~40 cm-3, the first peak corresponding to the entry into the magnetic tail, the second peak corresponding to the neutral sheet crossing from the northern to the sourthern tail lobe, and the third, somewhat smaller, peak corresponding to the outbound exit from the tail. Large depressions in the magnetic field strengths are observed coincident with each of the density peaks. These effects indicate that a dense plume of plasma is being carried downstream of Titan by the interaction with the rapidly rotating magnetosphere of Saturn. By equating the magnetic field pressure in the tail lobe to the plamsa pressure in the neutral sheet, the temperature of the plasma is estimated to be about 8600 ¿K. This low temperature suggest that the plasma originates from the ionosphere of Titan, probably forming a plume of plasma with a ϑ or H cross section extending downstream from Titan. Within the tail lobes, a second type of low-frequency electric field noise was observed, with characteristics very similar to a type of noise called broadband electrostatic noise, which is found in the earth's magnetic tail. As in the case of the earth, this noise is most intense near the outer boundary of the plasma sheet and is almost completely absent in the high-density region near the neutral sheet. |