HR: 11:05h
AN: P52B-04    [Abstracts]
TI: Plasma Production and Circulation in Saturn's (and Jupiter's?) Magnetosphere.
AU: * Rymer, A M
EM: abigail.rymer@jhuapl.edu
AF: Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Mauk, B H
EM: barry.mauk@jhuapl.edu
AF: Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Hill, T W
EM: hill@rice.edu
AF: Department of Physics and Astronomy, Rice University, Houston, TX 77005, United States
AU: Paranicas, C
EM: chris.paranicas@jhuapl.edu
AF: Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Mitchell, D G
EM: don.mitchell@jhuapl.edu
AF: Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Smith, H
EM: h.todd.smith@jhuapl.edu
AF: Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Christon, S P
EM: spchriston@aol.com
AF: Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Wilson, R J
EM: rjw@lanl.gov
AF: Los Alamos National Laboratory, Los Alamos, Los Alamos, NM 87545, United States
AU: Johnson, R E
EM: rej@virginia.edu
AF: University of Virginia, University of Virginia, Charlottesville, VA 22903, United States
AU: Andre, N
EM: nandre@rssd.esa.int
AF: Research and Scientific Support Department, Estec, Noordwijk, 2200 AG, Netherlands
AU: Sittler, E C
EM: edward.C.Sittler@nasa.gov
AF: NASA, Goddard Space Flight Centre, Greenbelt, MD 21405, United States
AU: Thorne, R M
EM: rmt@atmos.ucla.edu
AF: Department of Atmospheric and Oceanic Sciences, Los Angeles, Los Angeles, CA 90095, United States
AU: Coates, A J
EM: ajc@mssl.ucl.ac.uk
AF: Mullard Space Science Laboratory, Holmbury St Mary, Dorking, RH5 6NT, United Kingdom
AU: Young, D T
EM: dyoung@swri.edu
AF: Southwest Research Institute, SwRI, San Antonio, TX 78228, United States
AU: Santos-Costa, D
EM: dsantoscosta@swri.edu
AF: Southwest Research Institute, SwRI, San Antonio, TX 78228, United States
AU: Bolton, S J
EM: sbolton@swri.edu
AF: Southwest Research Institute, SwRI, San Antonio, TX 78228, United States
AU: Thomsen, M F
EM: mthomsen@lanl.gov
AF: Los Alamos National Laboratory, Los Alamos, Los Alamos, NM 87545, United States
AU: Dougherty, M K
EM: m.dougherty@imperial.ac.uk
AF: Department of Space and Atmospheric Physics, Imperial College, London, SW7 2AZ, United Kingdom
AB: Saturn has a distributed source of cold (<100 eV) electrons inside L ~ 12 associated with Saturn's satellites, rings, and extended neutral cloud. Phase space density analyses by Rymer et al. [2007a] have shown that the cold component has a local source, probably due to ionisation of the neutral cloud components. These cold electrons are heated to the observed energies through Coulomb collisions, and other interactions with ions, and transport slowly outward. Like Jupiter, magnetic flux lost through cold plasma outflow is balanced by the injection of hot outer magnetospheric plasma inward. Phase space density contours of the hot (> 100 eV) electron component at Saturn are consistent with a source in the outer magnetosphere which transports inward and heats adiabatically. Several studies have shown that small scale injection events are a ubiquitous feature of Saturn's magnetosphere [Burch et al., 2005, Hill et al., 2005, Leisner et al. 2005, André et al. 2005] and these are thought to be the source of the observed hot electron component. Rymer et al. [2007b] suggest that, along with losses to the neutral cloud, inwardly transported electrons turn around as they drift out of the small inflow channels and flow back to the outer magnetosphere – thus contributing to the hot electron component "butterfly" pitch angle distributions observed by Burch et al. [2007] and attributed to outward flow from an inner magnetospheric source. Here we summarise this electron recirculation picture as it currently stands and discuss how high energy in situ plasma observations and remote energetic neutral observations by MIMI along with proton observations by CAPS add to the current picture. There are significant differences in how Jupiter and Saturn behave in terms of electric and magnetic drift speeds; we will discuss to what extent our picture of Saturn's magnetosphere is true for Jupiter.
DE: 2700 MAGNETOSPHERIC PHYSICS (6939)
DE: 2730 Magnetosphere: inner
DE: 2740 Magnetospheric configuration and dynamics
DE: 2756 Planetary magnetospheres (5443, 5737, 6033)
DE: 7859 Transport processes
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting