Three types of SEP event (top to bottom): (a): VD event – SEP event with normal velocity dispersion; (b): nose-only event – SEP event with IVA features; (c): mixed event – a mixture of the two aforementioned types with clear separation between the first arriving VD and the later inverse features. The intensity unit is count/(s sr MeV cm²). These plots combine measurements from EPI-Hi/LET-A and HET-A, and the mean intensity averaged over all EPI-Lo apertures. The contour lines are calculated between the two vertical dashed lines.