Gaia-ESO Survey legacy overview
This VLT survey delivers the data to support a wide variety of studies of stellar populations, the evolution of dynamical systems, and stellar evolution. We complement Gaia by using GIRAFFE + UVES to find detailed abundances for at least 12 elements (Na, Mg, Si, Ca, Ti, V, Cr, Mn, Fe, Co, Sr, Zr, Ba) in ≥ 104 field stars with V ≤ 15.5 and for several other elements (including Li) for more metal-rich cluster stars. Depending on target S/N, and astrophysical parameters we typically probe the fundamental nucleosynthetic channels: nuclear statistical equilibrium (V, Cr, Mn, Fe, Co), and α-chain (Si, Ca, Ti). The radial velocity precision for this sample will be approximately 0.1 kms−1 to ≤ 5 kms−1, depending on target, with in each case the measurement precision being that required for the relevant astrophysical analysis. The data resolve the full phase-space distributions for large stellar samples in clusters. This makes it possible to identify, on both chemical and kinematic grounds, substructures that bear witness to particular merger or starburst events, and to follow the dissolution of clusters and the Galactic migration of field stars. The survey also supplies homogeneously determined chemical abundances, rotation rates and diagnostics of magnetic activity and accretion, for large samples of stars in clusters with precise distances, which can be used to challenge stellar evolution models. We are considerable effort in abundance calibration to ensure maximal future utility.
