.[Mg/Fe] ratio as a function of [Fe/H] for the combined sample. The solid red line shows the separation between thin and thick disk stars based on the [Mg/Fe] ratio, similar to Adibekyan et al. (2011): [Mg/Fe] = +0.19 for [Fe/H] ≤ −0.6, [Mg/Fe] = −0.217 × [Fe/H] + 0.06 for −0.6 < [Fe/H] ≤ 0, and [Mg/Fe] = +0.06 for [Fe/H] > 0. Stars above this line belong to the Galactic thick disk. The cyan circle is the anomalous star HD 65907.