Tokar, RL; Johnson, RE; Thomsen, MF; Delapp, DM; Baragiola, RA; Francis, MF; Reisenfeld, DB; ... Kurth, WS; + view all Tokar, RL; Johnson, RE; Thomsen, MF; Delapp, DM; Baragiola, RA; Francis, MF; Reisenfeld, DB; Fish, BA; Young, DT; Crary, FJ; Coates, AJ; Gurnett, DA; Kurth, WS; - view fewer (2005) Cassini observations of the thermal plasma in the vicinity of Saturn's main rings and the F and G rings. Geophysical Research Letters , 32 (14) , Article L14S04. 10.1029/2005GL022690.

Preview

PDF 2005GL022690.pdf Available under License : See the attached licence file. Download (181kB)

Abstract

The ion mass spectrometer on Cassini detected enhanced ion flux near Saturn's main rings that is consistent with the presence of atomic and molecular oxygen ions in the thermal plasma. The ring "atmosphere'' and "ionosphere'' are likely produced by UV photosputtering of the icy rings and subsequent photoionization of O-2. The identification of the O+ and O-2(+) ions is made using time-of-flight analysis and densities and temperatures are derived from the ion counting data. The ion temperatures over the main rings are a minimum near synchronous orbit and increase with radial distance from Saturn as expected from ion pick up in Saturn's magnetic field. The O-2(+) temperatures provide an estimate of the neutral O-2 temperature over the main rings. The ion mass spectrometer also detected significant O-2(+) outside of the main rings, near the F ring. It is concluded that between the F and G rings, the heavy ion population most likely consists of an admixture of O-2(+) and water group ions O+, OH+, and H2O+.

Download activity - last month

Export as XMLJSONCSV

Download activity - last 12 months

Export as XMLJSONCSV

Downloads by country - last 12 months

Export as JSONXMLCSV

Archive Staff Only

View Item