Multi-dimensional modeling of the diffusionrates of radiation belt electrons by whistle-mode chorus waves and simulations of resultant radiation belt electron loss timescales

Whistler-mode chorus waves are typical electromagnetic plasma wave mode in the Earth's inner magnetosphere, which play vital roles in the radiation belt dynamics. Chorus waves can scatter electrons toward the loss cone and then precipitate them into the atmosphere. Considered as an important source of relativistic electrons, they can also accelerate electrons from tens of keV to a few MeV. Therefore, efficient estimating the diffusion rates induced by chorus waves is important for optimizing the kinetic modeling and understanding the dynamic evolution of radiation belt electrons. In this study, we use Full Diffusion Code (FDC) to calculate the bounce-averaged pitch angle, energy, and cross diffusion rates for typical chorus wave models for electrons in the radiation belt, then establish a diffusion rates matrix for the Earth's inner magnetosphere L 2 similar to 7, the background environmental parameter alpha* 1 similar to 13, the pitch angle alpha(eq) 0 degrees similar to 90 degrees, and the energies E-k 10 eV similar to 10 MeV. On this basis, we further use linear interpolation method to quickly obtain the diffusion rates of radiation belt electrons scattered by the chorus waves under different L and alpha*, and verify the rationality and accuracy of the linear interpolation method by calculating the relative errors. Additionally, we investigate the loss timescales of radiation belt electron induced by chorus waves according to the diffusion rate matrix database, and establish an empirical model of the electron loss timescales with L, alpha*, and E-k as the input parameters. The electron loss timescales caused by the chorus waves can be quickly obtained from this model. Our results show that the computing time of the diffusion rates is significantly reduced by the construction of the diffusion rate matrix database with the usage of linear interpolation, and the empirical three-dimensional model can efficiently provide the wave-driven loss timescales on the radiation belt electrons. Briefly, these results can improve the efficiency of modeling the dynamics of the Earth's radiation belts and have great significance in the space weather forecasting.