State of the electron distributions at the time corresponding to the peak of the ν_obs = 15 GHz light curves for the expansion simulations with both radiative and adiabatic cooling enabled, and β_exp ranging [0.001, 0.3]. The vertical dashed lines correspond to the Lorentz factor of the electrons most contributing to the observed 15 GHz frequency. All the other parameters are the same as reported in Table 2.