eCite Digital Repository

Metallicities and radial velocities of five open clusters including a new candidate member of the Monoceros stream


Warren, SR and Cole, AA, Metallicities and radial velocities of five open clusters including a new candidate member of the Monoceros stream, Monthly Notices of the Royal Astronomical Society, 393, (1) pp. 272-296. ISSN 0035-8711 (2009) [Refereed Article]

Restricted - Request a copy

Copyright Statement

The definitive published version is available online at:

Official URL:

DOI: doi:10.1111/j.1365-2966.2008.14268.x


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 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 Ks-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 Ks-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: Berkeley81, Berkeley99, IC1311, King2 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.

Item Details

Item Type:Refereed Article
Keywords:techniques: spectroscopic-stars: abundances-stars: late-type-globular clusters: general-open clusters and associations: general
Research Division:Physical Sciences
Research Group:Astronomical sciences
Research Field:Galactic astronomy
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the physical sciences
UTAS Author:Cole, AA (Professor Andrew Cole)
ID Code:56317
Year Published:2009
Web of Science® Times Cited:34
Deposited By:Physics
Deposited On:2009-04-21
Last Modified:2010-03-25

Repository Staff Only: item control page