Extremely metal-poor stars from the SDSS

TL;DR

This paper reports progress in identifying extremely metal-poor stars from SDSS data, confirming 15 candidates with high-resolution spectroscopy, and exploring methods to extend the search to fainter targets using new instruments.

Contribution

It introduces new candidate stars with very low metallicity and evaluates the potential of upcoming observational techniques to find even fainter extremely metal-poor stars.

Findings

Confirmed 15 extremely metal-poor stars with UVES spectroscopy.

Identified 25 candidates with metallicities around or below -3.

Explored capabilities of X-shooter for fainter target observations.

Abstract

We give a progress report about the activities within the CIFIST Team related to the search for extremely metal-poor stars in the Sloan Digital Sky Survey's spectroscopic catalog. So far the search has provided 25 candidates with metallicities around or smaller -3. For 15 candidates high resolution spectroscopy with UVES at the VLT has confirmed their extremely metal-poor status. Work is under way to extend the search to the SDSS's photometric catalog by augmenting the SDSS photometry, and by gauging the capabilities of X-shooter when going to significantly fainter targets.