The Search for Extremely Low-Metallicity Stars in Dwarf Galaxies Using the NIR Ca II Triplet

Bibcode
2011EAS....48...13S
DOI
10.1051/eas/1148002
Starkenburg, E.; Hill, V.; Tolstoy, E.; González Hernández, J. I.; Irwin, M.; Helmi, A.; Boschman, L.; Francois, P.; Battaglia, G.; Jablonka, P.; Tafelmeyer, M.; Shetrone, M.; Venn, K.; de Boer, T.
Bibliographical reference

EAS Publications Series, Volume 48, 2011, pp.13-18

Advertised on:
7
2011
Number of authors
14
IAC number of authors
0
Citations
1
Refereed citations
1
Description
The NIR Ca II triplet has proven to be an important tool for quantitative spectroscopy. Here we present results of synthetic spectral analysis for the Ca II triplet for low-metallicity red giant stars, combined with observational data. Our results start to deviate strongly from the widely-used and linear empirical calibrations below [Fe/H] = -2. We provide a new calibration for Ca II triplet studies which is valid down until [Fe/H] = -4 and apply this new calibration to current data sets. We suggest that the classical dwarf galaxies are not so devoid of extremely low-metallicity stars as was previously thought and discuss preliminary results and possibilities for follow-up observations of these extremely low-metallicity candidates.
Type
Non-refereed

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