Statistical Study of Electric Pc5 Pulsations in the Inner Magnetosphere Observed by Cluster

Ultra-low frequency (ULF) waves in the Pc5 band are essential for the transport of electrons in the radiation belt and the transport of energy from the solar wind into the magnetosphere. Based on ∼14-year of electric field data from Cluster satellite, the spatial distributions of power spectral densities (PSD) of electric field ULF waves in the inner magnetosphere are statistically investigated, suggesting that PSDs of electric ULF wave increase with increasing L and depend on magnetic latitude (MLAT). PSDs of electric ULF wave are greater at noon for lower |MLAT| and at midnight for higher |MLAT|. Moreover, the L and MLAT dependent empirical formulas for the ULF magnetic and electric fields are provided, enabling the latitudinal effect in the radial diffusion evaluation. The results in this paper suggest a potential shift in the contribution to radial diffusion may occur between the magnetic and electric fields at different MLATs.