Spectroscopy of red giants in 12 open clusters

Near-infrared spectra of 133 red giant stars from 10 Galactic open clusters and two Galactic globular clusters spanning 2.2dex in metallicity and 11Gyr in age are presented. We combine this sample with 10 clusters from Cole and collaborators (2004MNRAS.347..367C) to investigate the CaII triplet line strengths and their relation to cluster metallicity and position along the red giant branch. We show that characterizing the stellar surface gravity using K_s_-band photometry (relative to the horizontal branch) taken from the Two Micron All-Sky Survey allows for metallicity measurements at least as precise as those derived using V- or I-band data. This has the great advantage that uniform photometry and reliable astrometry are available for a large number of clusters. Using K_s_-band photometry also reduces the effect of differential reddening within a given cluster. We find no significant evidence for age or metallicity effects to the linear CaII triplet-metallicity relationship over the small range in magnitudes studied when homogeneous reference metallicities are used. We derive the first spectroscopic metallicity and new radial velocity estimates for five open clusters: Berkeley 81, Berkeley 99, IC 1311, King 2 and NGC7044. King2 has an anomalous radial velocity compared with the local disc population. We discuss the possibility that it is part of the Monoceros tidal stream.

Cone search capability for table J/MNRAS/393/272/clusters (List of studied clusters)

Cone search capability for table J/MNRAS/393/272/tables3 (Sample of cluster giants and derived parameters)

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/393/272
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/393/272
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/393/272
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/MNRAS/393/272
Provenance
Creator Warren S.R.; Cole A.A.
Publisher CDS
Publication Year 2015
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Exoplanet Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy