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We report the discovery of nine metal-poor stars with high levels ofr-process enhancement (+0.81<[Eu/Fe]<+1.13), including six subgiants and threestars on the red horizontal branch. We also analyze four previously-knownr-process-enhanced metal-poor red giants. From this sample of 13 stars, we drawthe following conclusions. (1) High levels of r-process enhancement are foundin a broad range of stellar evolutionary states, reaffirming that thisphenomenon is not associated with a chemical peculiarity of red giantatmospheres. (2) Only 1 of 10 stars observed at multiple epochs shows radialvelocity variations, reaffirming that stars with high levels of r-processenhancement are not preferentially found among binaries. (3) Only 2 of the 13stars are highly-enhanced in C and N, indicating that there is no connectionbetween high levels of r-process enhancement and high levels of C and N. (4)The dispersions in [Sr/Ba] and [Sr/Eu] are larger than the dispersions in[Ba/Eu] and [Yb/Eu], suggesting that the elements below the second r-processpeak do not always scale with those in the rare earth domain, even within theclass of highly-r-process-enhanced stars. (5) The light-element (12<Z<30)abundances of highly-r-process-enhanced stars are indistinguishable from thosewith normal levels of r-process material at the limit of our data, 3.5 per cent(0.015 dex) on average. The nucleosynthetic sites responsible for the larger-process enhancements did not produce any detectable light-element abundancesignatures distinct from normal core-collapse supernovae.

Nine New Metal-Poor Stars on the Subgiant and Red Horizontal Branches with High Levels of r-process Enhancement