The dynamics of energetic electron fluxes in both the inner and the outer radiation belts is very important with respect to satellite protection, in particular for low and middle-orbit satellites. Based on the quasi-linear theory of gyroresonant wave-particle interaction, we compute the diffusion coefficients and loss timescales for radiation belt energetic electrons due to cyclotron resonance with artificial ELF/VLF emissions that are radiated through modulating the currents in the lower ionosphere by ground-based powerful high-frequency (HF) transmitter. We test the electron pitch-angle scattering in the outer zone, typically at L=4.6 (where the HAARP facility is located) and in the inner zone, typically at L=1.5. The results indicate that the electron loss timescales due to artificial injection of ELF/VLF waves in the inner and the outer radiation belts depend largely on the value of the cold-plasma parameter α*(∝B2/N0, where B is the ambient magnetic field and N0 the electron number density), the properties of wave frequency spectrum, the wave power and the electron energy in resonance with the waves. Generally, relativistic electrons in the outer zone are much easier to be precipitated into the atmosphere by artificial ELF/VLF whistler waves and lower-energy electrons (≤200keV) can undergo pitch-angle scattering more efficiently than higher-energy electrons (≥500keV). Since ELF/VLF waves can experience in situ amplification due to multiple magnetospheric reflections within the magnetospheric cavity, it can be reasonably expected that, under suitable situations, ground-based HF transmitters can provide feasible radiation power into the ionosphere to induce the injection of ELF/VLF waves into the inner magnetosphere, and consequently account for potential rapid removal of outer belt relativistic electrons in a timescale of from 1 to 3 days and of inner belt relativistic electrons that generally have a lifetime of 100 days or more in a timescale of the order of 10 days.
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