Transit‐Time Scattering Effect of Chorus Subpackets on Radiation Belt Electrons: Analytical Approach and Test Particle Simulations

Chorus waves are considered to play a significant role in the local acceleration of seed electrons to populate the outer radiation belt via wave–particle interactions in either quasilinear or nonlinear ways; however, which mechanism predominates in electron motion remains under debate. In this study, we adopted an analytical approach to investigate the transit‐time scattering of radiation belt electrons influenced by chorus waves containing subpackets. The analysis revealed that even for a coherent chorus wave, radiation belt electrons experience random diffusion when subpackets are present, a phenomenon verified as resonant diffusion. Our theoretical predictions were supported by test‐particle simulations. Finally, we discuss how the spatial scale and amplitude of chorus subpackets affect the final behavior of energetic electrons and elucidate the underlying physical processes. These results provide insights for assessing the contribution of chorus waves to the dynamic evolution of radiation belt electrons.