J/MNRAS/393/272 Spectroscopy of red giants in 12 open clusters (Warren+, 2009)
Metallicities and radial velocities of five open clusters including a new
candidate member of the Monoceros stream.
Warren S.R., Cole A.A.
<Mon. Not. R. Astron. Soc., 393, 272-296 (2009)>
=2009MNRAS.393..272W 2009MNRAS.393..272W
ADC_Keywords: Clusters, open ; Clusters, globular ; Stars, giant ;
Abundances ; Radial velocities
Keywords: techniques: spectroscopic - stars: abundances - stars: late-type -
globular clusters - general; open clusters and associations: general
Abstract:
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 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 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: 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.
Description:
We observed a sample of 10 Galactic open clusters and two Galactic
globular clusters with the multifibre spectrograph at the William
Herschel Telescope on La Palma.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
clusters.dat 72 22 List of studied clusters
tables3.dat 68 473 Sample of cluster giants and derived parameters
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See also:
J/A+AS/121/95 : Giant stars abundances in 24 clusters (Carretta+ 1997)
J/MNRAS/299/1 : BVI photometry in four open clusters (Sagar+, 1998)
Byte-by-byte Description of file: clusters.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Cluster Cluster name
14- 15 I2 h RAh Right ascension (J2000) (1)
17- 18 I2 min RAm Right ascension (J2000) (1)
20- 23 F4.1 s RAs Right ascension (J2000) (1)
25 A1 --- DE- Declination sign (J2000) (1)
26- 27 I2 deg DEd Declination (J2000) (1)
29- 30 I2 arcmin DEm Declination (J2000) (1)
32- 35 F4.1 arcsec DEs ? Declination (J2000) (1)
37- 41 F5.2 [Sun] [Fe/H] [-2.2/0.2]? Metallicity
43- 46 F4.2 [Sun] e_[Fe/H] [0.01/0.14]? rms uncertainty on [Fe/H]
48- 50 F3.1 kpc Dist [3/6.5]? Distance of cluster
52- 55 F4.1 Gyr Age [1/13] Cluster age
57- 61 F5.2 mag Ksmag Ks magnitude of red clump (RC)
63- 66 F4.2 mag e_Ksmag rms uncertainty on Ksmag
68- 70 A3 --- Ref References (2)
72 A1 --- C04 [*] * for Cole et al. (2004MNRAS.347..367C 2004MNRAS.347..367C)
clusters
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Note (1): Center of AF2/WYFFOS field.
Note (2): References to metallicity and age values as follows
1 = Carretta & Gratton (1997A&AS..121...95C 1997A&AS..121...95C, Cat. J/A+AS/121/95)
2 = Salaris & Weiss (2002A&A...388..492S 2002A&A...388..492S)
3 = Friel et al. (2002AJ....124.2693F 2002AJ....124.2693F)
4 = Salaris et al. (2004A&A...414..163S 2004A&A...414..163S)
5 = Sagar & Griffiths (1998MNRAS.299....1S 1998MNRAS.299....1S, Cat. J/MNRAS/299/1)
6 = Delgado et al. (1994AJ....108.2193D 1994AJ....108.2193D)
7 = Kaluzny (1989AcA....39...13K 1989AcA....39...13K)
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Byte-by-byte Description of file: tables3.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Cluster Cluster name
13- 28 A16 --- 2MASS 2MASS ID (HHMMSSss+DDMMSSs)
30- 34 F5.2 mag Ksmag [5.1/13.3] 2MASS Ks magnitude
36- 39 F4.2 mag e_Ksmag [0.01/0.05] rms uncertainty on Ksmag
41- 47 F7.2 km/s RV [-723/619] Radial velocity
49- 52 F4.2 km/s e_RV [0.01/5.32] rms uncertainty on RV
54- 58 F5.2 0.1nm SW(CaT) [-1.2/15] Calcium Triplet index (1)
60- 64 F5.2 0.1nm e_SW(CaT) [0.14/12] rms uncertainty on SW(CaT)
66- 68 A3 --- Notes Notes, 1=accepted star member (2)
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Note (1): The CaT index is taken as a linear combination of the
pseudo-equivalent widths of the three CaII lines
(λλ=8498.02, 8542.09, 8662.14Å).
Note (2): Notes as follows
1 = accepted stars
2 = radial velocity template
3 = radial velocity outlier or falling beyond the visual cluster bounds
(see text)
4 = TiO bands
5 = CN bands
6 = low quality spectra
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 08-Jun-2015