Distribution of the three mock populations on the T_eff and log g plane as synthesized (left panels) and derived by SP_Ace (right panel). The blue points, red crosses, and green triangles represent the thin, halo/thick disc, and accreted stars, respectively. The solid, dashed, and dotted black lines show isochrones at [M/H] = 0.0 dex and 5 Gyr, [M/H] = −1.0 dex and 10 Gyr, and [M/H] = −2.0 dex and 10 Gyr, respectively. The light gray errorbars represent the confidence intervals of the individual measurements. A missing errorbar indicates that the error is larger than the parameter grid.