J/MNRAS/463/580 Abundances of red giants in NGC6940 (Bocek+, 2016)
The chemical compositions and evolutionary status of red giants in the
open cluster NGC 6940.
Bocek Topcu G., Afsar M., Sneden C.
<Mon. Not. R. Astron. Soc., 463, 580-597 (2016)>
=2016MNRAS.463..580B 2016MNRAS.463..580B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, giant ; Equivalent widths
Keywords: stars: abundances - stars: atmospheres -
open clusters and associations: individual: NGC 6940 -
open clusters and associations: individual: Hyades
Abstract:
We present the high-resolution (R~=60000), high signal-to-noise ratio
(S/N~=120) spectroscopic analysis of 12 red giant members of the
Galactic open cluster NGC 6940. We applied Yonsei-Yale isochrones to
the colour-magnitude diagram, which suggested an age of 1.1Gyr for
the cluster with a turn-off mass of 2 M☉. Atmospheric parameters
(Teff, logg, [Fe/H], and ξt) were determined via equivalent
widths of FeI, FeII, TiI, and TiII lines. Calculated mean
metallicity of the cluster is <[Fe/H]≥0.04±0.02. We derived
abundances of α (Mg, Si, Ca), Fe-group (Sc, Ti, V, Cr, Mn, Fe,
Co, Ni, Cu, Zn), and n-capture (Y, La, Nd, Eu) elements to be about
solar. Light odd-Z elements Na and Al are slightly enhanced in MMU 108
and MMU 152 by ∼0.34 and ∼0.16dex, respectively. Abundances of light
elements Li, C, N, O, and 12C/13C ratios were derived from
spectrum syntheses of the LiI resonance doublet at 6707Å, [OI] line
at 6300Å, C2 Swan bandheads at 5164 and 5635Å, and strong
12,13CN system lines in the 7995-8040Å region. Most carbon
isotopic ratios are similar to those found in other solar-metallicity
giants, but MMU 152 has an unusual value of 12C/13C=6. Evaluation
of the LiCNO abundances and 12C/13C ratios along with the present
theoretical models suggests that all the red giants in our sample are
core-helium-burning clump stars.
Description:
This study is the second in this series of papers on the chemical
compositions RGs of OCs. Here we report the first detailed chemical
abundance analysis of NGC 6940, giving results for 12 RG members.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 84 12 Basic parameters of observed NGC 6940 RGs
table4.dat 32 218 Linelist of species
table5.dat 85 160 Equivalent width measurements of the
NGC 6940 RG members
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See also:
J/MNRAS/446/3562 : Abundances of red giants in NGC752 (Bocek Topcu+, 2015)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- Star Star name (MMUNNN)
7- 9 A3 --- n_Star Note on Star (1)
11- 12 I2 h RAh Right ascension (J2000)
14- 15 I2 min RAm Right ascension (J2000)
17- 22 F6.3 s RAs Right ascension (J2000)
24 A1 --- DE- Declination sign (J2000)
25- 26 I2 deg DEd Declination (J2000)
28- 29 I2 arcmin DEm Declination (J2000)
31- 35 F5.2 arcsec DEs Declination (J2000)
37- 41 F5.2 mag Bmag B magnitude
(Larsson-Leander, 1960StoAn..20i...1L 1960StoAn..20i...1L)
43- 47 F5.2 mag Vmag V magnitude
(Larsson-Leander, 1960StoAn..20i...1L 1960StoAn..20i...1L)
49- 52 F4.2 mag Kmag K magnitude (Cutri et al., 2003, Cat. II/246/)
54- 57 F4.2 mag VMAG0 Deredenned absolute V magnitude
59- 62 F4.2 mag B-V B-V colour index
64- 67 F4.2 mag (B-V)0 Deredenned B-V colour index
69- 72 F4.2 mag (V-K)0 Deredenned V-K colour index
74- 78 F5.2 mas/yr pmRA Proper motion along RA (pmRA*cosDE)
80- 84 F5.1 mas/yr pmDE Proper motion along DE
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Note (1): Note as follows:
c = Coordinates and proper motions from Hog et al.
(1998A&A...335L..65H 1998A&A...335L..65H, Cat. I/250)
d = Coordinates and proper motions from Hog et al.
(2000A&A...355L..27H 2000A&A...355L..27H, Cat. I/259)
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Species Species identification (1)
7- 13 F7.2 0.1nm lambda Wavelength in Angstroms
16- 20 F5.3 eV LEP ? Lower Excitation potential of the transition
21- 25 F5.2 [-] loggf ? Log of the oscillator strength
27- 29 A3 --- EW/Syn Method of analysis. Equivalent width measurement
or spectrum synthesis.
31- 32 A2 --- Ref Reference for log(gf) (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
(I=neutral, II=singly ionized).
Note (2): References as follows:
1 = KRUCZ
2 = Masseron et al. (2014A&A...571A..47)
3 = Brooke et al. (2014ApJS..210...23B 2014ApJS..210...23B)
4 = Sneden et al. (2014ApJS..214...26S 2014ApJS..214...26S)
5 = Allende Prieto et al. (2001ApJ...556L..63A 2001ApJ...556L..63A)
6 = NIST
7 = Lobel A. (2011CaJPh..89..395L 2011CaJPh..89..395L)
8 = VALD
9 = Ishigaki et al. (2012ApJ...753...64I 2012ApJ...753...64I)
10 = For & Sneden (2010AJ....140.1694F 2010AJ....140.1694F)
11 = Ivans, Inese et al. (2006ApJ...645..613I 2006ApJ...645..613I)
12 = Reddy et al. (2012MNRAS.419.1350R 2012MNRAS.419.1350R)
13 = Carrera & Pancino (2011A&A...535A..30C 2011A&A...535A..30C)
14 = Hamdani et al. (2000A&A...360..509H 2000A&A...360..509H)
15 = Smith & Raggett (1981JPhB...14.4015S 1981JPhB...14.4015S)
16 = Marsden et al. (1988JOSAB...5..606)
17 = Lawler et al.(2013ApJS..205...11L 2013ApJS..205...11L)
18 = Wood et al. (2013ApJS..208...27W 2013ApJS..208...27W)
19 = Lawler et al. (2014ApJS..215...20L 2014ApJS..215...20L)
20 = Sobeck et al. (2007ApJ...667.1267S 2007ApJ...667.1267S)
21 = Den Hartog et al. (2011ApJS..194...35D 2011ApJS..194...35D)
22 = Ruffoni et al. (2014MNRAS.441.3127R 2014MNRAS.441.3127R)
23 = Ramirez & Allende Prieto, C. (2011ApJ...743..135R 2011ApJ...743..135R)
24 = O'Brian et al. (1991JOSAB...8.1185O 1991JOSAB...8.1185O)
25 = Lambert et al. (1996ApJS..103..183L 1996ApJS..103..183L)
26 = Den Hartog et al. (2014ApJS..215...23D 2014ApJS..215...23D)
27 = Melendez & Barbuy (2009A&A...497..611)
28 = Lawler et al. (2015ApJS..220...13L 2015ApJS..220...13L)
29 = Wood et al. (2014ApJS..211...20W 2014ApJS..211...20W)
30 = Jacobson et al. (2007AJ....134.1216J 2007AJ....134.1216J)
31 = Reddy et al. (2015MNRAS.450.4301R 2015MNRAS.450.4301R)
32 = Lawler et al. (2001ApJ...556..452L 2001ApJ...556..452L)
33 = Den Hartog et al. (2003ApJS..148..543D 2003ApJS..148..543D)
34 = Den Hartog et al. (2002ApJS..141..255D 2002ApJS..141..255D)
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Species Species identification (1)
7- 13 F7.2 0.1nm lambda Wavelength
15- 19 F5.1 0.1pm MMU28 ? Equivalent width in milli-Angstroms (2)
21- 25 F5.1 0.1pm MMU30 ? Equivalent width in milli-Angstroms (2)
27- 31 F5.1 0.1pm MMU60 ? Equivalent width in milli-Angstroms (2)
33- 37 F5.1 0.1pm MMU69 ? Equivalent width in milli-Angstroms (2)
39- 43 F5.1 0.1pm MMU87 ? Equivalent width in milli-Angstroms (2)
45- 49 F5.1 0.1pm MMU101 ? Equivalent width in milli-Angstroms (2)
51- 55 F5.1 0.1pm MMU105 ? Equivalent width in milli-Angstroms (2)
57- 61 F5.1 0.1pm MMU108 ? Equivalent width in milli-Angstroms (2)
63- 67 F5.1 0.1pm MMU132 ? Equivalent width in milli-Angstroms (2)
69- 73 F5.1 0.1pm MMU138 ? Equivalent width in milli-Angstroms (2)
75- 79 F5.1 0.1pm MMU139 ? Equivalent width in milli-Angstroms (2)
81- 85 F5.1 0.1pm MMU152 ? 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
(I=neutral, II=singly ionized).
Note (2): The EW given for the synthesized line.
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History:
From electronic version of the journal
References:
Bocek Topcu et al., Paper I 2015MNRAS.446.3562B 2015MNRAS.446.3562B, Cat. J/MNRAS/446/3562
(End) Patricia Vannier [CDS] 30-Apr-2018