COMPREHENSIVE ANALYSIS OF ELECTRON OBSERVATIONS AT SATURN - VOYAGER-1AND VOYAGER-2

We present a comprehensive analysis of Voyager 1 and 2 electron observ ations within Saturn's magnetosphere. This analysis entails the mergin g of electron observations from the Plasma Science (PLS) experiment, t he Low Energy Charged Particle (LECP) experiment and the Cosmic Ray Sy stem (CRS) experiment. For each encounter, the three instruments combi ned allow us to compute the electron energy spectra over a wide range of energies from 10 eV to similar to 2 MeV between the closest approac hes and L = 18.5. The instruments use different technologies, differen t sensitivities, and different fields of view; however, we observe a s urprisingly good matching of the data sets on a 15-min timescale. The PLS-LECP-CRS spectra include the low-energy thermal component of the m agnetospheric plasma, the keV suprathermal electrons, and the high-ene rgy tail extending into the MeV energy range. From the combined spectr a, we compute a comprehensive set of macroscopic parameters (electron density, pressure, beta factor, and electron current at the spacecraft ): the analysis reveals a variety of radial gradients for these quanti ties and the corresponding electron populations. We also compute phase space densities over a wide range in energy and radial distances, ana lyzing local time symmetries, electron source distributions, and tempo ral variations of Saturn's magnetosphere. The ultimate goal of this st udy is to provide a comprehensive empirical model of the charged parti cle population within Saturn's magnetosphere. It will be used to suppo rt the development of the Cassini mission and to allow detailed planni ng of the tour design with regard to charged particle science and radi ation hazards.