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The variable extension of Saturn's electron radiation belts
Krupp, N.; Roussos, E.; Krimigis, S. M. +4 more
Contrary to the permanent MeV ion belts which are relatively stable in intensity over both short and long time scales and are modulated by a single Galactic Cosmic Ray driven source, the electron belts of Saturn appear to be much more complex in both structure and temporal evolution. In order to understand the responses of this system to the diffe…
A non-monotonic eddy diffusivity profile of Titan's atmosphere revealed by Cassini observations
Kammer, Joshua A.; Zhang, Xi; Li, Cheng +3 more
Recent measurements from the limb-view soundings of Cassini/CIRS and the stellar occultations from Cassini/UVIS revealed the complete vertical profiles of minor species (e.g., C2H2 and C2H4) from 100 to 1000 km in the atmosphere of Titan. In this study, we developed an inversion technique to retrieve the…
Evolution of electron pitch angle distributions across Saturn's middle magnetospheric region from MIMI/LEMMS
Livi, S.; Krupp, N.; Roussos, E. +5 more
We provide a global view of ~20 to 800 keV electron pitch angle distributions (PADs) close to Saturn's current sheet using observations from the Cassini MIMI/LEMMS instrument. Previous work indicated that the nature of pitch angle distributions in Saturn's inner to middle magnetosphere changes near the radial distance of 10RS. This work…
Plasma convection in the nightside magnetosphere of Saturn determined from energetic ion anisotropies
Krimigis, S. M.; Mitchell, D. G.; Carbary, J. F. +1 more
The Cassini Ion and Neutral Camera measures intensities of hydrogen and oxygen ions and neutral atoms in the Saturnian magnetosphere and beyond. We use the measured intensity spectrum and anisotropy of energetic hydrogen and oxygen ions to detect, qualify, and quantify plasma convection. We find that the plasma azimuthal convection speed relative …
A model of the spatial and size distribution of Enceladus' dust plume
Kriegel, Hendrik; Motschmann, Uwe; Schmidt, Jürgen +5 more
The structure of Enceladus' south polar plume of charged dust is studied by simulations of the dust grain dynamics. The model considers the Lorentz force and charging of the grains by the plasma environment within the plume. Simulated dust plumes are investigated by applying 10 selected sets of dust parameters that include variations of the grain …
Titan's plasma environment: 3D hybrid kinetic modeling of the TA flyby and comparison with CAPS-ELS and RPWS LP observations
Hartle, R. E.; Sittler, E. C.; Cooper, J. F. +2 more
In this report we discuss the global plasma environment of the TA flyby from the perspective of 3D hybrid modeling. In our model the background, pickup, and ionospheric ions are considered as particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our …
Corrigendum to “Evolution of Titan's major atmospheric gases and cooling since accretion” [Planet. Space Sci. 93-94 (2014) 41-53]
Gilliam, Ashley E.; Lerman, Abraham
Deriving the characteristics of warm electrons (100-500 eV) in the magnetosphere of Saturn with the Cassini Langmuir probe
Schippers, P.; Gurnett, D. A.; Lewis, G. R. +6 more
Though Langmuir probes (LP) are designed to investigate cold plasma regions (e.g. ionospheres), a recent analysis revealed a strong sensitivity of the Cassini LP measurements to hundreds of eV electrons. These warm electrons impact the surface of the probe and generate a significant current of secondary electrons, that impacts both the DC level an…