Two distinct halo populations in the solar neighborhood. II. (P. E. Nissen et al.)

Vol. 530
In section 5. Galactic structure, stellar clusters and populations

Two distinct halo populations in the solar neighborhood. II. Evidence from stellar abundances of Mn, Cu, Zn, Y, and Ba

Using VLT/UVES and NOT/FIES high-resolution spectrographs, the authors measured the abundances of heavy elements Mn, Cu, Zn, Y, and Ba in a sample of 78 halo dwarf stars in the solar neighborhood. They strengthened and expanded upon their previous result that there are two distinct populations in their sample, distinguished by the alpha element content. Including the properties of the heavy elements, the authors show that these two populations have likely origins in regions with different star formation properties, which supports current ideas about the build-up in the Galactic halo from multiple components.