Direct comparisons between RBSP (Van Allen Probes or Radiation Belt Storm Probes) and TWINS (Two Wide-angle Imaging Neutral-atom Spectrometers) for the main phase of two storms, March 17 and October 7, 2015, showed agreement between the in situ ion measurements and the ion spectra from the deconvolved energetic neutral-atom (ENA) measurements, except when O+ ions were significant. Spatial evolution of individual energy peaks in the ion spectra is studied using TWINS data. O+ ions are...