Wavy magnetodisk in Saturn's outer magnetosphere

[1] A simple wavy magnetodisk model can explain periodicities in energetic charged particles observed in Saturn's outer magnetosphere (>20 RS). The model's free parameters are the tilt of magnetodisk in inner magnetosphere (~1.8°), speed of outgoing spiral wave (~8 RS/h), critical radius (~10 RS), and period of rotation (10.64 h). The fidelity of the model is not judged by a least squares fit to the actual data, but rather by the model's accuracy in reproducing the Lomb periodogram of the periodicities. The model accurately simulates the main spectral feature near ~10.7 h plus a secondary (“dual”) period near ~10.95 h. The ability of the wavy magnetodisk with one period to produce the observed dual periodicity in the observations suggests that models having “dual” periods need not be invoked to explain some of the periodicities in Saturn's outer magnetosphere.