Toomre diagram of our sample stars. Continuous circles indicate constant peculiar space velocities, , at 50 (red), 70 (blue), and 200 (green) km s⁻¹, as in Bensby et al. (2003). Target sample stars are colour- and size-coded by the eccentricity of their orbit. Stars within 50 km s⁻¹ can be considered with high probability to belong to the thin disc, while stars with 70 km s⁻¹ < υ_pec < 200 km s⁻¹ are with high-probability thick disc stars. Stars with υ_pec between 50 and 70 km s⁻¹ can belong to both discs.