SEP intensity-to-shock parameter ratio for STA as a function of STB. Panel (a): I_e/p-to-V_HT ratio for STA as a function of I_e/p-to-V_HT ratio for STB. I_e/p is the ratio of electron intensity (I_e) to proton intensity (I_p). The energy band for electrons is fixed to 2.7–4 MeV and the energy band for protons is 13.6–15.1 MeV (crosses), 20.8–23.8 (triangles), 29.5–33.4 MeV (stars), 40–60 MeV (circles), and 60–100 MeV (plus signs). I_e and I_p are time-shifted according to the VDA before calculation of their ratio. Panel (b): I_p-to-M_A ratio for STA as a function of I_p-to-M_A ratio for STB. The proton intensities are the same as described in panel (a). In both panels the black line represents the case where these two ratios are equal. The colours are given according to the time in the event, from blue (start) to red (2H30 later).