Same as Fig. 4 for stars with metallicities between −0.4 and −0.9 dex. Yonsei-Yale evolutionary tracks for [Fe/H] = −0.68 and [α/Fe] = +0.3, labelled with mass in M_⊙. The step is 0.2 M_⊙ between 1.4 and 2.0 M_⊙. HD 220009 with M ≈ 0.8 M_⊙ has a metallicity closest to that of the shown tracks. HD 49933 and HD 22879 lie at the maximum and the minimum of the metallicity range, thus falling on higher (1.2 M_⊙) and lower mass (0.7 M_⊙) tracks, respectively, than those shown.