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Field-aligned currents in Saturn's southern nightside magnetosphere: Subcorotation and planetary period oscillation components
Coates, A. J.; Dougherty, M. K.; Alexeev, I. I. +6 more
We investigate magnetic data showing the presence of field-aligned magnetosphere-ionosphere coupling currents on 31 Cassini passes across Saturn's southern postmidnight auroral region. The currents are strongly modulated in magnitude, form, and position by the phase of the southern planetary period oscillations (PPOs). PPO-independent currents are…
Saturn's dynamic magnetotail: A comprehensive magnetic field and plasma survey of plasmoids and traveling compression regions and their role in global magnetospheric dynamics
Dougherty, M. K.; Thomsen, M. F.; Jackman, C. M. +8 more
We present a comprehensive study of the magnetic field and plasma signatures of reconnection events observed with the Cassini spacecraft during the tail orbits of 2006. We examine their "local" properties in terms of magnetic field reconfiguration and changing plasma flows. We also describe the "global" impact of reconnection in terms of the contr…
The location of magnetic reconnection at Saturn's magnetopause: A comparison with Earth
Frahm, R.; Masters, A.; Fuselier, S. A. +4 more
Data from the Cassini Electron Spectrometer are used to investigate the location of magnetic reconnection at Saturn's magnetopause. Heated, streaming electron distributions in the boundary layer on the magnetosheath side of the magnetopause are evidence of reconnection and an open magnetopause. A model for the location of reconnection is used to c…
The origin of Saturn's magnetic periodicities: Northern and southern current systems
Cowley, S. W. H.; Southwood, D. J.
The recent survey by Andrews et al. (2012) of the separate northern and southern ~10.7 h periodic magnetic signals in Saturn's magnetosphere limits very much their governing current systems. The existence of signals with pure or close to pure northern or southern periods in respective polar caps taken with the relatively narrow bandwidth of the si…
Properties of dust particles near Saturn inferred from voltage pulses induced by dust impacts on Cassini spacecraft
Gurnett, D. A.; Kempf, S.; Kurth, W. S. +5 more
The Cassini Radio and Plasma Wave Science (RPWS) instrument can detect dust particles when voltage pulses induced by the dust impacts are observed in the wideband receiver. The size of the voltage pulse is proportional to the mass of the impacting dust particle. For the first time, the dust impacts signals measured by dipole and monopole electric …
Turbulent magnetic field fluctuations in Saturn's magnetosphere
Saur, J.; Alexandrova, O.; von Papen, M.
We analyze the statistical properties of magnetic field fluctuations measured by the Cassini spacecraft inside Saturn's magnetosphere. We introduce Saturn's magnetosphere as a new laboratory for plasma turbulence, where background magnetic field is strong (1 nT<B0≤75 nT), fluctuations are weak (<δB/B> = 0.07), and the ion plasm…
Planetary period oscillations in Saturn's magnetosphere: Comparison of magnetic oscillations and SKR modulations in the postequinox interval
Dougherty, M. K.; Lamy, L.; Cowley, S. W. H. +1 more
We compare the properties of planetary period oscillations observed in Saturn kilometric radiation (SKR) and magnetospheric magnetic field data from Saturn equinox in August 2009 to July 2013. As shown previously, the southern and northern oscillation periods converged across equinox from ~10.8 h and ~10.6 h, respectively, during southern summer, …
Plasma flows in Saturn's nightside magnetosphere
Thomsen, M. F.; Wilson, R. J.; Tokar, R. L. +1 more
The plasma properties, especially the flow parameters, obtained from numerical integration of Cassini Plasma Spectrometer (CAPS) Ion Mass Spectrometer measurements during intervals when the CAPS field of view encompassed both inward and outward flow directions relative to corotation are examined for nightside data (18-06 local time) during 2006, 2…
Ion densities and magnetic signatures of dust pickup at Enceladus
Dougherty, Michele K.; Saur, Joachim; Kriegel, Hendrik +5 more
Encedalus' plume of charged dust has been shown to strongly modify the plasma structures. Therefore, we analyze the magnetic signatures of dust to constrain the dust plume. For the first time, the mutual feedback between the nanograins and their plasma environment is investigated. Our model combines plasma simulations by means of the A.I.K.E.F. (A…
Multi-instrument analysis of plasma parameters in Saturn's equatorial, inner magnetosphere using corrections for corrections for spacecraft potential and penetrating background radiation
Persoon, A. M.; Crary, F.; Mitchell, D. G. +4 more
We use a forward modeling program to derive one-dimensional isotropic plasma characteristics in Saturn's inner, equatorial magnetosphere using a novel correction for the spacecraft potential and penetrating background radiation. The advantage of this fitting routine is the simultaneous modeling of plasma data and systematic errors when operating o…