Bolometric luminosity L_bol,1d (top-left) and UVW1-band magnitudes M_UVW1,1d (top-right), V-band magnitudes M_V,1d (bottom-left) as a function of initial kinetic energy E_kin,coll and the Doppler velocity V_Hα,1d (bottom-right) at maximum absorption measured in the Hα line profile as a function of V_rel. All these values are measured at 1 d since collision. We distinguish collisions with different masses using different markers and those with different impact parameters using different colors. The black and blue diagonal lines show the relations given by the fitting formulae in Equations (4)–(7) for b = 0.1 and 0.5, respectively. In the top panels and bottom-left panel, the empty crosses represent values for giant collisions considered in Ryu et al. (2024b).