Fig. 2
From: Formation of electron radiation belts at Saturn by Z-mode wave acceleration
Distribution of wave normal angle for Z-mode waves. These calculations assume a cold plasma index of refraction and are calculated only where density values are available for the data in Fig. 1. The index of refraction is based on the observed value of circular polarization, fpe and fce. Calculations were done where the apparent circular polarization Stokes parameter, V, is >0.5; below this value the calculation is not reliable. The data is shown in blue as number of occurrences normalized to the maximum number of occurrences. The thick black line shows a Gaussian fit to the data with a peak power at a wave normal angle of 21.88°, a width of 17.18°
