J/MNRAS/419/1350 Red giants abundances in 4 open clusters (Reddy+, 2012)
Comprehensive abundance analysis of red giants in the open clusters
NGC 752, 1817, 2360 and 2506.
Reddy A.B.S., Giridhar S., Lambert D.L.
<Mon. Not. R. Astron. Soc., 419, 1350-1361 (2012)>
=2012MNRAS.419.1350R 2012MNRAS.419.1350R
ADC_Keywords: Clusters, open ; Stars, giant ; Equivalent widths
Keywords: stars: abundances - Galaxy: abundances -
open clusters and associations: individual: NGC 752 -
open clusters and associations: individual: NGC 1817 -
open clusters and associations: individual: NGC 2360 -
open clusters and associations: individual: NGC 2506
Abstract:
We have analysed high-dispersion echelle spectra (R≳50000) of
red giant members for four open clusters to derive abundances for many
elements. The spread in temperatures and gravities being very small
among the red giants nearly the same stellar lines were employed
thereby reducing the random errors. The errors of average abundance
for the cluster were generally in the range 0.02-0.07dex. Our
present sample covers Galactocentric distances of 8.3-10.5kpc. The
[Fe/H] values are -0.02±0.05 for NGC 752, -0.07±0.06 for
NGC 2360, -0.11±0.05 for NGC 1817 and -0.19±0.06 for NGC 2506.
Abundances relative to Fe for elements from Na to Eu are equal within
measurement uncertainties to published abundances for thin-disc giants
in the field. This supports the view that field stars come from
disrupted open clusters.
Description:
Clusters were selected from the New catalogue of optically visible
open clusters and candidates (Dias et al., 2002, Cat. B/ocl).
Observations were conducted during 1999 February 6-10 with Tull
echelle coude spectrograph on the 2.7-m Harlan J. Smith telescope at
the McDonald observatory.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 64 14 The observed stars
table6.dat 45 2430 The line list for all program stars from each of
the OCs presented in the paper
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See also:
B/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2012)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Cluster Cluster name
10- 13 I4 --- Star Star number within the cluster
15- 16 I2 h RAh Right ascension (J2000.0)
18- 19 I2 min RAm Right ascension (J2000.0)
21- 25 F5.2 s RAs Right ascension (J2000.0)
27 A1 --- DE- Declination sign (J2000.0)
28- 29 I2 deg DEd Declination (J2000.0)
31- 32 I2 arcmin DEm Declination (J2000.0)
34- 38 F5.2 arcsec DEs Declination (J2000.0)
40- 44 F5.2 mag Vmag V magnitude
46- 50 F5.2 mag B-V B-V colour index
52- 56 F5.1 km/s HRV Heliocentric radial velocity
58- 60 F3.1 km/s e_HRV rms uncertainty on HRV
62- 64 I3 --- S/N Signal-to-noise ration at 6000Å
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Cluster Cluster name
10- 13 I4 --- Star Star number within the cluster
15- 21 F7.2 0.1nm lambda Wavelength λ in Angstroms
23- 27 F5.1 --- Ion Species identification (1)
29- 33 F5.2 eV LEP Lower Excitation potential of the transition
35- 39 F5.2 [-] log(gf) Log of the oscillator strength
41- 45 F5.1 0.1pm EW Equivalent width in milli-Angstroms (2)
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Note (1): The integer component of the species ID indicates the atomic
number, and the decimal component indicates the ionization state
(0=neutral, 1=singly ionized).
Note (2): The EW given for the synthesized line (MnI, CuI, BaII and EuII,
CeII and SmII) is the blend equivalent width.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 12-Jun-2012