Dust Plasma Environment between Saturn’s Rings and Mimas’ L Shell

Abstract:

We will present a new analysis of the available data on the extension of Saturn’s ring atmosphere into the magnetosphere beyond the A-ring outer edge (Johnson et al. 2006) out to the orbit of Mimas. This is an interesting region in Saturn’s magnetosphere containing the F and G rings and penetrated by the E-ring and the Enceladus neutral torus. This analysis will include a comparison of the Cassini Plasma Spectrometer (CAPS) plasma data, Radio and Plasma Wave Spectrometer (RPWS) plasma wave observations, RPWS Langmuir Probe (LP) observations and Cassini Dust Analyzer (CDA). The central focus will be on the dust plasma interactions. Specific attention will be paid to the SOI data for which there are considerable differences between the ion and electron densities (Elrod et al., 2012) while for other close flybys inside Mimas’ L shell such differences are less obvious but the electron data appear to be highly variable. Using previous identifications of nm particles (Jones et al., 2010) inferred from CAPS data and micron sized particles that can be detected by CDA (Kempf et al., 2006) and the RPWS plasma wave dust impact signatures (Kurth et al., 2006) we will attempt to infer the full particle size distribution between the A-ring and Mimas. These nm to micron sized particles can accumulate considerable charge and under certain circumstances could account for the radial trend in the ion density described in Elrod et al. (2014) a critical issue in preparation for the Cassini proximal orbits.

References:

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Jones, G. H., et al., Geophys. Res. Lett., 36, L16204, 2009.

Kempf, S., U. Beckmann, R. Srama, M. Horanyi, S. Auerd, E. Grun, Planet. Space Sci., 54, 999–1006, 2006.

Kurth, W. S., T.F. Averkamp, D.A. Gurnett, Z. Wang, Planet. Space Sci., 54, 988–998, 2006.