Finding the Most Metal-poor Stars of the Galactic Halo with the Hamburg/ESO Objective-prism Survey
نویسنده
چکیده
I review the status of the search for extremely metal-poor halo stars with the Hamburg/ESO objective-prism survey (HES). 2 194 candidate metal-poor turnoff stars and 6 133 giants in the magnitude range 14 . B . 17.5 have been selected from 329 (out of 380) HES fields, covering an effective area of 6 400 square degrees in the southern extragalactic sky. Moderate-resolution followup observations for 3 200 candidates have been obtained so far, and ∼ 200 new stars with [Fe/H] < −3.0 have been found, which trebles the total number of such extremely low-metallicity stars identified by all previous surveys. We use VLT-UT2/UVES, Keck/HIRES, Subaru/HDS, TNG/SARG, and Magellan/MIKE for high-resolution spectroscopy of HES metal-poor stars. I provide an overview of the scientific aims of these programs, and highlight several recent results.
منابع مشابه
An Automated Search for Metal-Poor Halo Stars in the Hamburg/ESO Objective-Prism Survey
An automated search for metal-poor stars is carried out in the course of the Hamburg/ESO objective-prism survey (HES), which covers the full southern sky at Galactic latitudes |b| & 30◦. As the HES reaches ∼ 1 magnitude deeper and covers areas of the sky which have not been touched by the HK Survey of Beers and collaborators, the total survey volume of the HES represents an increase by a factor...
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