Solar wind - radiation belt coupling across scales

The response of the outer radiation belt to large-scale variations in the solar wind is an active field of research. In this work, we use electron flux measurement from the full 7 years of the Van Allen probes mission along with solar wind properties measurements from the OMNI database at L1 and THEMIS/ARTEMIS spacecraft to investigate how the electron flux in the outer radiation belt responds to variations in the solar wind parameters across temporal scales. We find that electron flux has multiple periodicities correlated with those of the solar wind. At the largest temporal scales, we observe 0.5-year, 27-days, and 13.5-days periodicities which are most prominent near the declining phase of the solar cycle. This is consistent with the Axial Effect where the solar magnetic field is aptly modeled as a tilted dipole and the Earth encounters the fast solar wind at the observed periodicities. In addition, we observe modulations in the electron flux at lower time scales (<= 1 day). The interpretation of the higher frequency periodicity and the study of the effects of various mesoscale structures such as HFAs, foreshock bubbles, and magnetosheath jets, on the electron flux in the outer radiation belt, is still under investigation.