Median light curves at 1.4 GHz during merger events for z < 1 (solid blue circles) and z > 1 (solid red circles) as a function of time with respect to the core-passage. The median main progenitor cluster mass is M_200,1 = 2.77 × 10¹⁴ M_⊙ and 2.34 × 10¹³ M_⊙, respectively. Solid triangles correspond, in each case, to mergers with impact parameters b < 200 kpc measured at z_start. Fitting functions are shown as solid and dashed lines (see Section 4.4.2 for details).