Kinematics and chemical abundances of metal-poor stars in the Galactic outer halo

A survey of chemical abundances for Galactic metal-poor stars, which are likely constituents of the outer part of the halo, is currently in progress. The sample analysed so far is comprised of 26 metal-poor ([Fe/H] < -1) stars, whose estimated orbits reach >5 kpc above and below the Galactic plane. Using these sample stars selected based on their kinematics, we carried out the high-resolution spectroscopy with Subaru/HDS and obtained their chemical abundances. The detailed abundance pattern of the outer halo stars has important clues for the progenitor systems populating the Galactic outer halo. The current status of our survey is reported.