Fig. 9.

Van Allen Probe B/EMFISIS observations of a electron density at the satellite position and b average plasma mass for 02:10–03:10 UT on 12 September 2017, which are the identical to Fig. 6a and b. Van Allen Probe B/HOPE observations of c–e the energy-time diagrams of H⁺, He⁺, and O⁺ ions, f partial densities of H⁺ (black), He⁺ (blue), and O⁺ (red) ions calculated from ion fluxes over the energy range of 1 eV–50 keV, and g average plasma mass calculate from the partial densities, for 02:10–03:10 UT