HR: 10:35h
AN: SM52A-02 INVITED    [Abstracts]
TI: Energetic Particles in Saturn's Magnetotail
AU: * Mitchell, D G
EM: don.mitchell@jhuapl.edu
AF: Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Carbary, J F
EM: jim.carbary@jhuapl.edu
AF: Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Krupp, N
EM: krupp@linmpi.mpg.de
AF: 4Max-Planck Institut für Sonnensystemforschung, Max-Planck- Strasse 2, Lindau, D-37191, Germany
AU: Krimigis, S M
EM: Tom.Krimigis@jhuapl.edu
AF: Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AU: Hamilton, D C
EM: dch@umd.edu
AF: Department of Physics, University of Maryland, University Blvd, College Park, MD 20742, United States
AU: Kane, M
EM: mark_kane@yahoo.com
AF: Research Consulting Group, Inc., 1411 Saratoga Dr, Bel Air, MD 21014, United States
AB: Energetic particle measurements in Saturn's magnetotail reveal a magnetotail dominated by Saturn's rotational dynamics as far back in the tail as 60 Rs, rarely but sometimes spectacularly disrupted by tail reconnection events. Although Cassini spent little time in the tail, and even less at the location of the tail current sheet, the time spent there revealed a pattern of very regular encounters with the energetic particles that fill the current sheet, usually once every Saturn rotation. Carbary et al. 2007a, b show that energetic electrons reappear every rotation when the spacecraft is sufficiently close to the current sheet location, and further that they lie along a spiral in longitude when mapped into the SKR coordinate system (Kurth et al., 2007). Energetic ions are also observed in the same locations, with a mix of hydrogen and oxygen not very different from that observed in the magnetosphere between 10 and 20 Rs. These ions generally display velocities approximately in the corotation direction, but with magnitudes well below rigid corotation (Kane et al., 2007, manuscript in preparation). Two other classes of energetic particle events are also seen in the magnetotail. The first consists of energetic ion and electron beams, likely accelerated in the auroral zone over downward current regions. The second are those generated in tail reconnection events (e.g., Jackman et al., 2007; Hill et al. 2007). We will give examples of all of these phenomena, including both in situ measurements and ENA images/movies. Carbary, J.~F., Mitchell, D.~G., Krimigis, S.~M., Hamilton, D.~C., Krupp, N., Charged particle periodicities in Saturn's outer magnetosphere, Journal of Geophysical Research (Space Physics) 112, 6246 {2007JGRA..11206246C} 2007a Carbary, J. F., D. G. Mitchell, S. M. Krimigis, and N. Krupp (2007), Evidence for spiral pattern in Saturn's magnetosphere using the new SKR longitudes, Geophys. Res. Lett., 34, L13105, doi:10.1029/2007GL030167 2007b Kurth, W. S., A. Lecacheux, T. F. Averkamp, J. B. Groene, and D. A. Gurnett (2007), A Saturnian longitude system based on a variable kilometric radiation period, Geophys. Res. Lett., 34, L02201, doi:10.1029/2006GL028336. M. Kane, D. G. Mitchell, J. F. Carbary, and S. M. Krimigis, Ion convective anisotropies detected by the Cassini INCA experiment in Saturn's magnetosphere, manuscript in preparation, 2007. Jackman, C. M., C. T. Russell, D. J. Southwood, C. S. Arridge, N. Achilleos, and M. K. Dougherty, (2007), Strong rapid dipolarizations in Saturn's magnetotail: In situ evidence of reconnection, Geophys. Res. Lett., 34, L11203, doi:10.1029/2007GL029764. Hill, T.W., M.F. Thomsen, M.G. Henderson, R.L. Tokar, A.J. Coates, H.J. McAndrews, G.R. Lewis, D.G. Mitchell, C.M. Jackman, F.J. Crary, D.T. Young, M.K. Dougherty, C.T. Russell, (2007), Plasmoids in Saturn's Magnetotail, submitted, J. Geophys. Res., 2007JA012626, 2007.
DE: 2720 Energetic particles: trapped
DE: 2740 Magnetospheric configuration and dynamics
DE: 2744 Magnetotail
DE: 5443 Magnetospheres (2756)
DE: 6275 Saturn
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting