J/A+A/592/A70 Gaia FGK stars: low-metallicities candidates (Hawkins+, 2016)
Gaia FGK benchmark stars: new candidates at low-metallicities.
Hawkins K., Jofre P., Heiter U., Soubiran C., Blanco-Cuaresma S.,
Casagrande L., Gilmore G., Lind K., Magrini L., Masseron T., Pancino E.,
Randich S., Worley C.C.
<Astron. Astrophys. 592, A70 (2016)>
=2016A&A...592A..70H 2016A&A...592A..70H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, F-type ; Stars, G-type ; Stars, K-type ; Abundances, [Fe/H]
Keywords: stars: fundamental parameters - techniques: spectroscopic - standards
Abstract:
We have entered an era of large spectroscopic surveys in which we can
measure, through automated pipelines, the atmospheric parameters and
chemical abundances for large numbers of stars. Calibrating these
survey pipelines using a set of "benchmark stars" in order to evaluate
the accuracy and precision of the provided parameters and abundances
is of utmost importance. The recent proposed set of Gaia FGK benchmark
stars has up to five metal-poor stars but no recommended stars within
-2.0<[Fe/H]←1.0dex. However, this metallicity regime is
critical to calibrate properly.
In this paper, we aim to add candidate Gaia benchmark stars inside of
this metal-poor gap. We began with a sample of 21 metal-poor stars
which was reduced to 10 stars by requiring accurate photometry and
parallaxes, and high-resolution archival spectra.
The procedure used to determine the stellar parameters was similar to
the previous works in this series for consistency. The difference was
to homogeneously determine the angular diameter and effective
temperature (Teff) of all of our stars using the Infrared Flux Method
utilizing multi-band photometry. The surface gravity (logg) was
determined through fitting stellar evolutionary tracks. The [Fe/H] was
determined using four different spectroscopic methods fixing the Teff
and logg from the values determined independent of spectroscopy.
Description:
The line-by-line Fe abundance of the metal-poor candidate Gaia FGK
benchmark stars. This table also includes the line-by-line equivalent
widths (EW) and NLTE corrections.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sources.dat 85 10 General information on metal-poor benchmark
candidates selected (from table 1 of the paper)
tablea1.dat 116 71 BD+26 4251 Fe abundance measurements for each
line and node
tablea2.dat 116 66 HD 102200 Fe abundance measurements for each
line and node
tablea3.dat 116 73 HD 106038 Fe abundance measurements for each
line and node
tablea4.dat 116 68 HD 126681 Fe abundance measurements for each
line and node
tablea5.dat 116 64 HD 175305 Fe abundance measurements for each
line and node
tablea6.dat 116 76 HD 196892 Fe abundance measurements for each
line and node
tablea7.dat 116 76 HD 201891 Fe abundance measurements for each
line and node
tablea8.dat 116 64 HD 218857 Fe abundance measurements for each
line and node
tablea9.dat 116 73 HD 241253 Fe abundance measurements for each
line and node
tablea10.dat 116 72 HD 298986 Fe abundance measurements for each
line and node
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See also:
III/281 : Gaia FGK benchmark stars v2.1 (Jofre+, 2018)
J/A+A/564/A133 : Gaia FGK benchmark stars: metallicity (Jofre+, 2014)
J/A+A/566/A98 : Gaia FGK benchmark Stars - Library (Blanco-Cuaresma+, 2014)
J/A+A/582/A81 : Gaia FGK benchmark stars: abundances (Jofre+, 2015)
Byte-by-byte Description of file: sources.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Star Star name
11- 12 I2 h RAh Right ascension (J2000)
14- 15 I2 min RAm Right ascension (J2000)
17- 21 F5.2 s RAs Right ascension (J2000)
23 A1 --- DE- Declination sign (J2000)
24- 25 I2 deg DEd Declination (J2000)
27- 28 I2 arcmin DEm Declination (J2000)
30- 34 F5.2 arcsec DEs Declination (J2000)
36- 39 I4 K Teff Effective temperature (1)
41- 42 I2 K e_Teff rms uncertainty on Teff (1)
44- 45 I2 --- o_Teff Number of references in PASTEL database
for Teff
47- 50 F4.2 [cm/s2] logg Surface gravity (1)
52- 55 F4.2 [cm/s2] e_logg rms uncertainty on logg (1)
57- 58 I2 --- o_logg Number of references in PASTEL database
for logg
60- 64 F5.2 [-] [Fe/H] Metallicity (1)
66- 69 F4.2 [-] e_[Fe/H] rms uncertainty on [Fe/H] (1)
71- 72 I2 --- o_[Fe/H] Number of references in PASTEL database
for [Fe/H]
74- 81 A8 --- Table Name of the table with Fe abundance
measurements
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Note (1): The stellar parameters for each star were compiled using the PASTEL
database (Soubiran et al., 2010, Cat. B/pastel).
The Teff, e_Teff, logg, e_logg, [Fe/H] and e_[Fe/H] represent the mean and
dispersion of the stellar parameters from N references in the PASTEL database.
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Byte-by-byte Description of file (# headlines): tablea*.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Element Element and Ion state
7- 13 F7.2 0.1nm lambda Wavelength of line used in the abundance
determination
17- 22 F6.3 0.1pm Mean Equivalent width from all nodes
26- 30 F5.3 --- Mean Fe abundance derived for that line across
all nodes
33- 38 F6.3 --- NLTE ?=-0.0 NLTE correction for that line (1)
44- 50 F7.3 0.1pm EW(EPI) ?=-99.990 Equivalent width obtained by the
EPINARBO method (2)
53- 59 F7.3 0.1pm EW(BOL) ?=-99.990 Equivalent width obtained by the
Bologna method (2)
62- 68 F7.3 0.1pm EW(ULB) ?=-99.990 Equivalent width obtained by the
ULB method (2)
71- 77 F7.3 0.1pm EW(iSPEC) ?=-99.990 Equivalent width obtained by the
iSPEC method (2)
83- 89 F7.3 --- A(EPI) ?=-99.990 abundance obtained by the
EPINARBO method (2)
92- 98 F7.3 --- A(BOL) ?=-99.990 abundance obtained by the
Bologna method (2)
101-107 F7.3 --- A(ULB) ?=-99.990 abundance obtained by the
ULB method (2)
110-116 F7.3 --- A(iSPEC) ?=-99.990 abundance obtained by the
iSPEC method (2)
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Note (1): if there was no NLTE correction for a specific line it is
indicated by -0.00.
Note (2): if a method had no abundance measurement of a given line, the value
was set to -99.99.
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Acknowledgements:
Keith Hawkins, khawkins(at)ast.cam.ac.uk
Institute of Astronomy, University of Cambridge
References:
Heiter et al., Paper I 2015A&A...582A..49H 2015A&A...582A..49H
Blanco-Cuaresma et al., Paper II 2014A&A...566A..98B 2014A&A...566A..98B, Cat. J/A+A/566/A98
Jofre et al., Paper III 2014A&A...564A.133J 2014A&A...564A.133J, Cat. J/A+A/564/A133
Jofre et al., Paper IV 2015A&A...582A..81J 2015A&A...582A..81J, Cat. J/A+A/582/A81
Hawkins et al., Paper V 2016A&A...592A..70H 2016A&A...592A..70H, Cat. J/A+A/592/A70
Jofre et al., 2017A&A...601A..38J 2017A&A...601A..38J
(End) K. Hawkins [Inst. of Astronomy, Cambridge], P. Vannier [CDS] 27-Jul-2016