Spectroscopy of Pristine EMP star candidates

The catalogue consists of a total of 1007 stars, and includes 146 rediscoveries of metal-poor stars already presented in previous surveys, 707 new very metal-poor stars with [Fe/H]<-2.0, and 95 new extremely metal-poor stars with [Fe/H]<-3.0.

We provide a spectroscopic [Fe/H] for every star in the catalogue, and [C/Fe] measurements for a subset of the stars (10 per cent with [Fe/H]<-3 and 24 per cent with -3<[Fe/H]<-2) for which a carbon determination is possible, contingent mainly on the carbon abundance, effective temperature and signal-to-noise ratio of the stellar spectra. We find an average carbon enhancement fraction ([C/Fe]>=+0.7) of 41+/-4 per cent for stars with -3<[Fe/H]<-2 and 58+/-14 per cent for stars with [Fe/H]<-3, and report updated success rates for the Pristine survey of 56 per cent and 23 per cent to recover stars with [Fe/H]<-2.5 and <-3, respectively.