SAGA -Stellar Abundances for Galactic Archeology Database-
Short Name:
SAGA
Date:
14 Nov 2019 03:49:35
Publisher:
JVO
Description:
We describe the construction of a database of extremely metal-poor (EMP) stars
in the Galactic halo whose elemental abundances have been determined. Our
database contains detailed elemental abundances, reported equivalent widths,
atmospheric parameters, photometry, and binarity status, compiled from papers in
the recent literature that report studies of EMP halo stars with [Fe/H] <
-2.5. The compilation procedures for this database have been designed to
assemble the data effectively from electronic tables available from online
journals. We have also developed a data retrieval system that enables data
searches by various criteria, and permits the user to explore relationships
between the stored variables graphically. Currently, our sample includes 1212
unique stars (many of which are studied by more than one group) with more than
15000 individual reported elemental abundances, covering all of the relevant
papers published by December 2007. We discuss the global characteristics of the
present database, as revealed by the EMP stars observed to date. For stars with
[Fe/H] < -2.5, the number of giants with reported abundances is larger than
that of dwarfs by a factor of two. The fraction of carbon-rich stars (among the
sample for which the carbon abundance is reported) amount to ~30 % for [Fe/H]
< -2.5. We find that known binaries exhibit different distributions of
orbital period, according to whether they are giants or dwarfs, and also as a
function of metallicity, although the total sample of such stars is still quite
small.
