HRD for the observed sample in Wd1. The colour of the symbols encodes the binary status based on RV measurements: confirmed binaries from Ritchie et al. (2022, red), candidate binaries identified in this work (orange), likely single stars (blue), and stars without RV measurements (grey). The shape of the symbols indicates whether the star had been analysed previously by Ritchie et al. (2022, triangles), while circles mark stars analysed for the first time in this work. Z = 0.02 isochrones (Yusof et al. 2022) for ages log t [yr] = 6.0-7.0 are overplotted (coloured curves).