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Description
Radial diffusion is a key process controlling the dynamics of relativistic electrons in planetary radiation belts. In Earth’s outer belt, the radial diffusion coefficient (Dll) is typically derived from well-established analytical formulations that relate electromagnetic field fluctuations, particularly ultra-low frequency (ULF) waves, to stochastic radial transport. For Saturn, by contrast, available Dll descriptions are often reduced to simple power-law dependences on radial distance, without explicit consideration of the magnetospheric conditions that may control particle transport. However, the direct application of these formulations to Saturn remains uncertain due to the planet’s distinct magnetospheric environment, including rapid rotation, the presence of moons and rings, and the lack of continuous in-situ or upstream measurements. This work investigates how classical terrestrial formulations of radial diffusion can be adapted to Saturn’s relativistic electron belt. The study revisits the analytical derivations used to construct Dll from the Fokker-Planck equation, with emphasis on the assumptions that relate the radial diffusion coefficient to wave power and other associated parameters. It then assesses how this framework must be adapted for Saturn, identifying which components can be retained and which require reformulation to account for the planet’s magnetospheric environment and the processes governing its electron radiation belt dynamics. The objective is to establish a physically consistent pathway for extending the terrestrial radial diffusion theory to Saturn. This provides a theoretical foundation for future efforts aimed at quantifying radial diffusion and developing parameterizations for Saturn’s radiation belts.