An Automated Search for Metal-Poor Halo Stars in the Hamburg/ESO Objective-Prism Survey
نویسندگان
چکیده
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 of 4.5 compared to the HK Survey. Because of the limited availability of telescope time for spectroscopic follow-up observations, we will focus on a search for the most metal-poor, unevolved stars. We present a simulation study of the HES selection function P (BJ , Teff, [Fe/H], log g) for metal-poor stars, and results from a first follow-up campaign at the ESO-NTT.
منابع مشابه
Finding the Most Metal-poor Stars of the Galactic Halo with the Hamburg/ESO Objective-prism Survey
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 ...
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