Radio lightcurves at 6 GHz by varying various parameters: injected energy from the magnetar E_inj (panel (a)), mass of the merger ejecta M_ej (panel (b)), initial spin-down luminosity ﹩{L}_{\mathrm{sd},0}﹩ (panel (c)), density of the surrounding medium n (panel (d)), fraction of the post-shock energy density in magnetic field ϵ_B (panel (e)), and fraction of the post-shock energy density in electron ϵ_e (panel (f)). The fiducial parameters are (plotted with blue dashed–dotted lines): ﹩{E}_{\mathrm{inj}}={10}^{52}﹩ erg, ﹩{M}_{\mathrm{ej}}={10}^{-3}{M}_{\odot }﹩, ﹩{L}_{\mathrm{sd},0}={10}^{48}﹩ erg s⁻¹, n = 1.0 cm⁻³, ﹩{\epsilon }_{B}={10}^{-2}﹩, ϵ_e = 0.1, and p = 2.3.