HR: 0830h
AN: P21C-09    [Abstracts]
TI: Molecular Oxygen Ions Within Saturn's Inner Magnetosphere as Observed by Cassini: Initial Results
AU: * Sittler, E C
EM: edward.c.sittler@nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Road, Code 612.2, Greenbelt, MD 20771 United States
AU: Johnson, R E
EM: rej@virginia.edu
AF: University of Virginia, Department of Engineering, Thornton Hall, Charlottesville, VA 22904 United States
AU: Smith, H T
EM: hts4f@virginia.edu
AF: University of Virginia, Department of Engineering, Thornton Hall, Charlottesville, VA 22904 United States
AU: Baragiola, R
EM: rb9a@virginia.edu
AF: University of Virginia, Department of Engineering, Thornton Hall, Charlottesville, VA 22904 United States
AU: Francis, M F
EM: mff7d@virginia.edu
AF: University of Virginia, Department of Engineering, Thornton Hall, Charlottesville, VA 22904 United States
AU: Chornay, D
EM: dennis.j.chornay.1@gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Road, Code 612.2, Greenbelt, MD 20771 United States
AU: Shappirio, M D
EM: mark.d.shappirio@nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Road, Code 612.2, Greenbelt, MD 20771 United States
AU: Simpson, D G
EM: david.g.simpson@nasa.gov
AF: NASA Goddard Space Flight Center, 8800 Greenbelt Road, Code 612.2, Greenbelt, MD 20771 United States
AU: Reisenfeld, D
EM: dan.reisenfeld@umontana.edu
AF: University of Montana, Department of Physics and Astronomy, 32 Campus Drive, Missoula, MT 59812 United States
AU: Thomsen, M F
EM: mthomsen@lanl.gov
AF: Los Alamos National Laboratory, Mail Stop D-466, Los Alamos, NM 87545 United States
AU: Tokar, R L
EM: rlt@lanl.gov
AF: Los Alamos National Laboratory, Mail Stop D-466, Los Alamos, NM 87545 United States
AU: Crary, F
EM: fcrary@swri.edu
AF: Southwest Research Institute, Division of Space Science and Engineering, 6220 Culebra Road, San Antonio, TX 28510 United States
AU: McComas, D J
EM: dmccomas@swri.edu
AF: Southwest Research Institute, Division of Space Science and Engineering, 6220 Culebra Road, San Antonio, TX 28510 United States
AU: Young, D T
EM: dyoung@swri.edu
AF: Southwest Research Institute, Division of Space Science and Engineering, 6220 Culebra Road, San Antonio, TX 28510 United States
AB: We will present initial results of our analysis of molecular oxygen ions within Saturn's inner magnetosphere as observed by the Cassini Plasma Spectrometer (CAPS) experiment. As reported in Young et al. (2005) the O2+ is a minor species in the magnetosphere, but is dominant over the main rings (Tokar et al., 2005). This analysis, confined outside Mimas' L shell, will be built around the work of Sittler et al. (2005) who computed fluid parameters of protons and water group ions within Saturn's inner plasmasphere. A non-linear analysis of the composition data will be used. We will constrain the analysis by requiring the O2+ to be comoving with the water group ions. This will allow us to make estimates of ion density and temperature for the O2+ along the various Cassini trajectories through Saturn's inner magnetosphere. Molecular oxygen is important because it can be produced by gas phase processes, but can also be a signature of the decomposition of icy surfaces by radiolysis and photolysis (Johnson et al 2003; 2004). Therefore, similar to the observation of an ozone-like feature on Dione and Rhea (Noll et al. 1997), the observation of molecular oxygen ions can be a marker for the radiation-induced erosion of ice grains and icy bodies within Saturn's magnetosphere. Our results will examine the formation and redistribution of molecular oxygen within the inner magnetosphere.
DE: 2732 Magnetosphere interactions with satellites and rings
DE: 2756 Planetary magnetospheres (5443, 5737, 6030)
DE: 2768 Plasmasphere
DE: 5465 Rings and dust
DE: 6280 Saturnian satellites
SC: Planetary Sciences [P]
MN: 2005 Joint Assembly