J/ApJ/764/78 Oxygen abundances in nearby FGK stars (Ramirez+, 2013)
Oxygen abundances in nearby FGK stars and the Galactic chemical evolution of
the local disk and halo.
Ramirez I., Allende Prieto C., Lambert D.L.
<Astrophys. J., 764, 78 (2013)>
=2013ApJ...764...78R 2013ApJ...764...78R
ADC_Keywords: Abundances ; Radial velocities ; Stars, G-type ; Stars, masses ;
Stars, ages ; Equivalent widths
Keywords: Galaxy: disk; Galaxy: evolution; Galaxy: formation; stars: abundances;
stars: atmospheres; stars: fundamental parameters
Abstract:
Atmospheric parameters and oxygen abundances of 825 nearby FGK stars
are derived using high-quality spectra and a non-local thermodynamic
equilibrium analysis of the 777nm OI triplet lines. We assign a
kinematic probability for the stars to be thin-disk (P1), thick-disk
(P2), and halo (P3) members. We confirm previous findings of
enhanced [O/Fe] in thick-disk (P2>0.5) relative to thin-disk
(P1>0.5) stars with [Fe/H]≲-0.2, as well as a "knee" that connects
the mean [O/Fe]-[Fe/H] trend of thick-disk stars with that of
thin-disk members at [Fe/H]≳-0.2. Nevertheless, we find that the
kinematic membership criterion fails at separating perfectly the stars
in the [O/Fe]-[Fe/H] plane, even when a very restrictive kinematic
separation is employed. Stars with "intermediate" kinematics
(P1<0.7, P2<0.7) do not all populate the region of the
[O/Fe]-[Fe/H] plane intermediate between the mean thin-disk and
thick-disk trends, but their distribution is not necessarily bimodal.
Halo stars (P3>0.5) show a large star-to-star scatter in
[O/Fe]-[Fe/H], but most of it is due to stars with Galactocentric
rotational velocity V←200km/s; halo stars with V>-200km/s follow an
[O/Fe]-[Fe/H] relation with almost no star-to-star scatter. Early
mergers with satellite galaxies explain most of our observations, but
the significant fraction of disk stars with "ambiguous" kinematics and
abundances suggests that scattering by molecular clouds and radial
migration have both played an important role in determining the
kinematic and chemical properties of solar neighborhood stars.
Description:
We have analyzed 897 high resolution (R≳45000) and high
signal-to-noise ratio (S/N≳100) spectra of 825 stars, in addition to
10 solar (daysky and asteroid) spectra. Most of these spectra were
taken by us, but we also used data from public archives.
Our spectra have been acquired using four instrument/telescope
combinations: McD/TS2 (R. G. Tull Coude spectrograph, 2.7m Telescope
at McDonald Observatory), HET/HRS (High Resolution Spectrograph, 9.2m
Hobby-Eberly Telescope), VLT/UVES (UV-Visual Echelle Spectrograph, 8m
Very Large Telescope), and ESO/FEROS (Fiber-feb Extended Range Optical
Spectrograph, ESO 1.52m Telescope).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 93 825 Basic and Kinematic Data
table3.dat 31 144 Iron Line List
table4.dat 76 825 Atmospheric Parameters
table5.dat 70 825 Age and Mass
table6.dat 62 825 Oxygen Abundance
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See also:
B/pastel : The PASTEL catalogue (Soubiran+, 2010-)
V/130 : Geneva-Copenhagen Survey of Solar neighbourhood III (Holmberg+, 2009)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
III/190 : WEB Catalog of Radial Velocities (Duflot+ 1995)
I/238 : Yale Trigonometric Parallaxes, Fourth Edition (van Altena+ 1995)
V/89 : Ages, Metallicities, Galactic Orbit of F stars (Marsakov+ 1995)
III/184 : 3rd Bibliog. Cat. of Stellar Radial Vel. (Barbier-Brossat+, 1994)
III/21 : General Catalogue of Stellar Radial Velocities (Wilson, 1953)
J/A+A/562/A71 : Abundances of solar neighbourhood dwarfs (Bensby+, 2014)
J/ApJ/756/46 : Lithium abundances in HIP stars (Ramirez+, 2012)
J/A+A/535/A42 : Metal rich stars in solar neighbourhood (Trevisan+, 2011)
J/A+A/531/A8 : Activity indexes and velocities for 890 stars (Jenkins+, 2011)
J/A+A/530/A138 : Geneva-Copenhagen survey re-analysis (Casagrande+, 2011)
J/ApJ/735/41 : Carbon and oxygen abundances in FGK stars (Petigura+, 2011)
J/A+A/508/L17 : Abundances in solar analogs (Ramirez+, 2009)
J/A+A/465/271 : Oxygen abundances in nearby stars (Ramirez+, 2007)
J/MNRAS/367/1329 : Elemental abundances for 176 stars (Reddy+, 2006)
J/PASJ/57/65 : CNO abundances of solar-type stars (Takeda+, 2005)
J/PASJ/57/27 : Atmospheric parameters of nearby F-K stars (Takeda+, 2005)
J/PASJ/57/13 : High-dispersion spectra of nearby F-K stars (Takeda+, 2005)
J/A+A/430/165 : Radial velocities for 6691 K and M giants (Famaey+, 2005)
J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)
J/A+A/420/183 : Spectro. survey in solar neighborhood (Allende Prieto+ 2004)
J/MNRAS/340/304 : [X/Fe] of Galactic disc F and G dwarfs (Reddy+, 2003)
J/AJ/124/1144 : Orbits of 171 single-lined spectrosc. binaries (Latham, 2002)
J/A+A/394/927 : Age-metallicity relation for nearby stars (Ibukiyama+, 2002)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Star name
12- 16 F5.2 mag Vmag [-0.05/11] V band magnitude (1)
18- 23 F6.2 mas Plx [2.7/797]? Parallax (2)
25- 29 F5.2 mas e_Plx ? Uncertainty in Plx (2)
31- 36 F6.1 km/s RVel [-296/186.1] Radial velocity (3)
38- 41 F4.1 km/s e_RVel [0.5/36] Uncertainty in RVel (3)
43- 48 F6.1 km/s UVel Velocity towards the Galactic center
50- 53 F4.1 km/s e_UVel Uncertainty in UVel
55- 60 F6.1 km/s VVel Velocity in the direction of galactic rotation
62- 66 F5.1 km/s e_VVel Uncertainty in VVel
68- 73 F6.1 km/s WVel Velocity toward the North Galactic Pole
75- 78 F4.1 km/s e_WVel Uncertainty in WVel
80- 83 F4.2 --- P1 Thin-disk kinematic probability
85- 88 F4.2 --- P2 Thick-disk kinematic probability
90- 93 F4.2 --- P3 Halo kinematic probability
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Note (1): Visual magnitudes V and (B-V) colors were extracted mainly from
the General Catalogue of Photometric Data (GCPD; Mermilliod et al.
1997A&AS..124..349M 1997A&AS..124..349M). For the few stars without Johnson's photometry
in the GCPD, we searched the Hipparcos catalog (Perryman et al. 1997,
Cat. I/239) for V and (B-V) values observed from the ground.
Note (2): Most of our sample stars are included in the Hipparcos catalog.
We used the parallaxes and proper motions from the new reduction by
van Leeuwen (2007, Cat. I/311). For HD 144070, which is not included
in the Hipparcos catalog, we used the ground-based measurement listed
in the van Altena et al. (1995, Cat. I/238) compilation. The stars HIP
7751 and HIP 55288 are each known to be in wide visual binary systems.
Their secondaries, for which we also have spectroscopic data and have
therefore been analyzed, are fainter and not listed in the Hipparcos
catalog. In these cases we adopted the parallaxes of the primaries for
the secondaries. Our spectroscopic analysis confirmed the true binary
nature of these two pairs; the radial velocities and elemental
abundances we infer are in agreement for the two stars in each pair.
Note (3): Radial velocities were adopted from published catalogs and our
own measurements. In Ramirez et al. 2007 (J/A+A/465/271), we provided
radial velocities for a large fraction of our sample stars. For these
objects, the radial velocities adopted here are from that paper. For
the other stars, we used the average of values from the following
sources: Barbier-Brossat et al. 1994 (III/184), Duflot et al. 1995
(III/190), the GCS (Nordstrom et al. 2004, Cat. V/130), Ramirez et al.
2009 (J/A+A/508/L17), Jenkins et al. 2011 (J/A+A/531/A8), Latham et
al. 2002 (J/AJ/124/1144), and our own measurements. Other sources for
few stars, which were not found in any of the works listed above, are
Famaey et al. 2005 (J/A+A/430/165), Evans & Wild (1969Obs....89...15E 1969Obs....89...15E)
and Wilson 1953 (III/21).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 7 F7.2 0.1nm lambda [4576.3/7711.8] Wavelength; in Angstroms
9- 13 A5 --- ID Fe species identifier
15- 19 F5.3 eV ExPot [0.08/5] Excitation potential
21- 25 F5.2 [-] log(gf) [-5/-0.2] Log of oscillator strength
27- 31 F5.1 0.1pm EW [9/123] Equivalent width (in mÅ)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Star name
12- 15 I4 K Teff [4215/6989] Effective temperature
17- 19 I3 K e_Teff [22/129] Uncertainty in Teff
21- 24 F4.2 [cm/s2] logg [1.2/4.8] Log of the surface gravity
26- 29 F4.2 [cm/s2] e_logg [0/0.3] Uncertainty in logg
31- 35 F5.2 [Sun] [Fe/H] [-2.8/0.4] Metallicity
37- 40 F4.2 [Sun] e_[Fe/H] [0.02/0.3] Uncertainty in [Fe/H]
42- 45 F4.2 km/s Vt [0/2.5] Turbulent velocity
47- 47 A1 --- f_Vt [+] Vt adopted (4)
49- 53 F5.2 [Sun] [Fe/H]1 Metallicity derived from FeI lines
55- 58 F4.2 [Sun] e_[Fe/H]1 Uncertainty in [Fe/H]1
60- 64 F5.2 [Sun] [Fe/H]2 Metallicity derived from FeII lines
66- 69 F4.2 [Sun] e_[Fe/H]2 Uncertainty in [Fe/H]2
71- 76 A6 --- Sample Sample name (giant, main, manual or noplx) (5)
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Note (4): "+" indicates that the adopted microturbulent velocity for the star
was obtained from the linear regression (Equation 5).
Note (5): A few stars (18) presented several different difficulties when
attempting to measure their atmospheric parameters. In some cases very
few lines were available, making the determination of vt extremely
difficult. These could be not only very metal-poor stars, but also
objects for which our spectra are of relatively low quality. In other
cases, the published parallaxes returned unphysical logg values, as
confirmed from inspection of the gravity-sensitive MgIb features at
5180Å or from their odd location in the H-R diagram. For these
stars (the "manual" sample), whenever possible, we constrained Teff
and/or logg from excitation and ionization balance; otherwise we
adopted the averages of values found in the literature, as compiled by
Soubiran et al. (2010, Cat. B/pastel). See section 3.4.
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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- 10 A10 --- Name Star name
12- 16 F5.2 Gyr Age [0.4/14.7]?=-1 Stellar age
18- 22 F5.2 Gyr e1Age Lower 1σ uncertainty in Age
24- 28 F5.2 Gyr E1Age Upper 1σ uncertainty in Age
30- 34 F5.2 Gyr e2Age Lower 2σ uncertainty in Age
36- 40 F5.2 Gyr E2Age Upper 2σ uncertainty in Age
42- 46 F5.3 Msun M [0.6/2.2]?=0 Stellar mass
48- 52 F5.3 Msun e1M Lower 1σ uncertainty in Mass
54- 58 F5.3 Msun E1M Upper 1σ uncertainty in Mass
60- 64 F5.3 Msun e2M Lower 2σ uncertainty in Mass
66- 70 F5.3 Msun E2M Upper 2σ uncertainty in Mass
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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- 10 A10 --- Name Star name
12- 15 F4.2 [-] L7772 [0/9.6] LTE derived [O/H] abundance
from 7772Å line
17- 20 F4.2 [-] L7774 LTE derived [O/H] abundance from 7774Å line
22- 25 F4.2 [-] L7775 LTE derived [O/H] abundance from 7775Å line
27- 30 F4.2 [-] N7772 NLTE derived [O/H] abundance from 7772Å line
32- 35 F4.2 [-] N7774 NLTE derived [O/H] abundance from 7774Å line
37- 40 F4.2 [-] N7775 NLTE derived [O/H] abundance from 7775Å line
42- 46 F5.2 [Sun] [O/H]L [-1.6/0.7] Differential LTE derived
[O/H] abundance
48- 51 F4.2 [Sun] e_[O/H]L Uncertainty in [O/H]LTE
53- 57 F5.2 [Sun] [O/H]N [-3.9/0.6] Differential NLTE derived
[O/H] abundance
59- 62 F4.2 [Sun] e_[O/H]N Uncertainty in [O/H]NLTE
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 20-Mar-2014