Luminosity in L_⊙ vs time in years of SSPs (left panel) with the Salpeter IMF (in number of stars per mass interval) with exponent -2.5 and total SSP mass of 5.826 M_⊙. The chemical compositions of the SSPs and associated color code are the same as in Fig. A.1. Model galaxies with infall calculated by the authors (right panel). The color code indicates the total baryonic mass of the galaxy in M_⊙ whose value is also displayed in the label of each curve. The timescale of gas infall is τ = 1 Gyr. The peak in luminosity corresponds to the maximum SFR. The galaxy models are described by D’Onofrio & Chiosi (2023).