Comparison of the marginalised posterior distributions for the three fits of the afterglow of GW 170817 presented in Sect. 4, which differ only by the treatment of the radiative processes: “no SSC” in blue; “SSC (Thomson)” in green; “SSC (with KN)” in orange. The first two rows show the inferred distributions of the free model parameters. The last row shows the distributions of several quantities derived from these parameters: The true energy of the jet E₀ (see Eq. (5)), the ratio θ_v/θ_c, and the four quantities used in the conditions for single-peaked light curves from Beniamini et al. (2020b) and described in Sect. 2.2, log(θ_cΓ₀^c), 8b/a, $-b\frac{log{\theta }_{\mathrm{c}}}{log{\mathrm{\Gamma }}_0^{\mathrm{c}}}$, and $(b-1)\frac{log({\theta }_{\mathrm{v}}/{\theta }_{\mathrm{c}})}{log\left({\mathrm{\Gamma }}_0^{\mathrm{c}}{\theta }_{\mathrm{c}}\right)}$.