L‐Value and Energy Dependence of 0.1–50 keV O+, He+, and H+ Ions for CME and CIR Storms Over the Entire Van Allen Probes Era

Abstract

AbstractOur studies report the first observation of L‐value and energy sorted correlation of differential fluxes of 0.1–50 keV O+, He+, and H+ ions with different geophysical parameters for 29 Coronal Mass Ejected (CME) and 40 Corotating Interaction Region (CIR)‐driven geomagnetic storms during the entire Van Allen Probes era. For both solar wind drivers, ions with ≥1 keV energies show more variability in response to the solar wind changes, while the lower energy (<1 keV) ions are relatively stable. During the in‐storm interval, O+ ions show maximum flux enhancement and become further prominent during CME storms. O+ ion (≥10 keV) fluxes show good correlation with − VswBz, and Sym‐H index during CME‐driven storms in the L ∼2.5–5.5. Apart from this, the average duration of persistence (〈Δt〉) for enhanced fluxes is higher for CIR‐driven storms with >> at E ≤ 50 keV in the L ∼2.5–5.5. Moreover, the observed value of 〈Δt〉i (where i is O+, H+ or He+) increases with the increasing L. We discuss the plausible mechanisms to provide a comprehensive overview of L‐values and energy sorted O+, He+ and H+ ion dynamics for two different categories of solar wind drivers.