interaction regions (CIRs) within 1 au. Five of these CIRs were also observed by ACE at 1
au, allowing for comparisons of the suprathermal ion intensities and spectra at different
radial distances. Only subtle modulations of the 4 He spectral slopes are observed between
Solar Orbiter and ACE. Additionally, the radial gradients of 226− 320 keV/nuc 4 He ion
intensities between Solar Orbiter and ACE are similar to that of 1.53 MeV H reported by Van …