tokens: of the local inventory, nearby solar-type stars provide particular insight from high signal-to-noise, high-resolution spectroscopy, such as stellar masses and ages. Most or possibly all of the scatter in the barium-to-iron abundances among the Population II and intermediate-disc stars, as we learn in this work, is subject to former mass transfer from white dwarf companions, and, if accounted for, discloses a very different perspective on the underlying core-collapse supernovae nucleosynthesis. Likewise, non-single sources cause false stellar parameters and hence scatter or potentially even false trends in the derived elemental abundances, if their individual components are not treated as such, which is often commonplace. There are numerous examples in the literature, and sources like the intermediate-disc star HD 117635 in P1 or the Population II star HD 34297 in Fig. 1 below in this work, just two of them. On the other hand, it is frequently found that towards the metal-rich end the Population I and II disc star sequences progressively coalesce with their iron versus α-chain elemental abundances. This is – for many reasons – important to know, and it may be of some relevance that the stars of P1 and the present, extended sample, as we see, do not comply with a systematic trend of this kind in terms of their magnesium and iron enrichment. Figure 1. Modelling of the Fe i line λ6200.321 in the composite spectrum of the spectroscopic binary HD 34297 ( P ≃ 2 yr) with its Aa and Ab components being Doppler-displaced at Δ v r (Aa–Ab) =+28.9 km s −1 in this 2017 November 28 observation. Stellar parameters for the spectrum synthesis (dark blue) are as given in the legend. The light blue-dotted curves denote abundance changes of Δ[Fe/H] = ±0.10 dex. Individual line profiles of the Aa and Ab components are given by the red-dotted curves. In Sections 2 and 3 we briefly discuss the characteristics of the underlying spectroscopic observations and the model atmosphere analyses. The very centrepiece of our work follows in Section 4 with the analyses and related key aspects of the Population II and intermediate-disc stars. As in P1, these comprise about one-third of the final 42 pc ancient star sample and several findings as they become apparent at the present, intermediate stage of the survey will be the subject of Section 5 . Population I stars, which in the course of the analyses are identified as such, and hence not part of the survey, are presented in the Appendix. 2 OBSERVATIONS With reference to a Gaia -based 42 pc parent sample, our strategy to cover an unbiased, complete subset of more than a hundred ancient solar-type Population II (τ ≥ 12 Gyr) and intermediate-disc stars (τ ≃ 10 Gyr) within that volume has been described in detail in P1. The spectroscopic observations that we present in this second work on the survey were all secured in 2017 with the FEROS échelle spectrograph (Kaufer et al. 1999 ) at the La Silla Observatory in Chile, most of them
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