Exploring the Galaxy’s halo and very metal-weak thick disc with SkyMapper and Gaia DR2

  title={Exploring the Galaxy’s halo and very metal-weak thick disc with SkyMapper and Gaia DR2},
  author={Giacomo Cordoni and Gary S Da Costa and David Yong and A D Mackey and Anna Fabiola Marino and Stephanie Monty and Thomas Nordlander and John E. Norris and Martin Asplund and Michael S. Bessell and Andrew R. Casey and Anna Frebel and Karin Lind and Simon J. Murphy and Brian P. Schmidt and X. D. Gao and T. Xylakis-Dornbusch and Anish M. Amarsi and Antonino P. Milone},
  journal={Monthly Notices of the Royal Astronomical Society},
In this work we combine spectroscopic information from the \textit{SkyMapper survey for Extremely Metal-Poor stars} and astrometry from Gaia DR2 to investigate the kinematics of a sample of 475 stars with a metallicity range of $ -6.5 \leq \rm [Fe/H] \leq -2.05$ dex. Exploiting the action map, we identify 16 and 40 stars dynamically consistent with the \textit{Gaia Sausage} and \textit{Gaia Sequoia} accretion events, respectively. The most metal-poor of these candidates have metallicities of… 

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