Electron distributions (red lines) composed from the shock reflected electrons (green lines) with different background Maxwellian distribution (blue lines). Top: the distributions composed from the distribution of reflected electrons with ⟨ E_r ⟩ = 1.68 keV and T_s = 6 MK (case 4, Table 1) with Maxwellian distributions having different electron densities n_B = 0.01, 0.1, and 1.0 and fixed temperature T_B = 5 MK. Middle: the distributions composed from the distribution of reflected electrons (case 4) with the Maxwellian distributions having n_B/n_s = 0.1 and temperature T_B = 2–6 MK. Bottom: the distributions composed from different distributions of reflected electrons (⟨ E_r ⟩ = 1.19, 1.52, and 1.84 keV) (case 1, 3, and 5) with the Maxwellian distribution with T_B = 5 MK and n_B/n_s = 0.1.