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Krimigis & Armstrong 1982
Krimigis, S.M. and Armstrong, T.P. (1982). Two-component proton spectra in the inner Saturnian magnetosphere. Geophysical Research Letters 9: doi: 10.1029/GL009i010p01143. issn: 0094-8276.

The Low Energy Charged Particle (LECP) experiment onboard the Voyager-2 spacecraft performed extensive measurements of energetic (~28 keV≲Ep≲150 MeV; ~22 keV≲Ee≲20 MeV) protons and electrons during spacecraft passage through the inner magnetosphere of Saturn in August 1981. Analysis of the measurements inside the orbits of Enceladus and Mimas reveals the presence of a two-component proton spectrum consisting of a low-energy population at ≲500 keV identified for the first time and described by dj/dE = KE2.5, and a high-energy part at E>16 MeV whose spectral form is similar to that expected from cosmic ray neutron albedo decay (CRAND), as previously inferred by the Pioneer-11 investigators from integral measurements. In addition, there exist large fluxes of high (>1.5 MeV) and low (22 to 35 keV) energy electrons (~3.5¿105 and ~1.1¿105 cm-2sec-1sr-1, respectively) throughout this region. The pitch angle distribution of low energy protons changes from a simple sin2/3 &agr; dependence to one where intensities near 90¿ become depleted as the spacecraft approached the planet's ring plane at ~2.88 RS. It is likely that the pitch angle depletion is due to proton interactions with the tenuous G-ring. These observations also resolve a number of uncertainties regarding the presence of energetic protons and electrons inside the orbits of Enceladus and Mimas, arising from the analysis of Pioneer-11 measurements.

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Geophysical Research Letters
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American Geophysical Union
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