J/A+A/598/A100 Abundances of disk giants: O, Mg, Ca and Ti (Jonsson+, 2017)
Abundances of disk and bulge giants from high-resolution optical spectra:
I. O, Mg, Ca, and Ti in the solar neighborhood and Kepler field samples.
Jonsson H., Ryde N., Nordlander T., Pehlivan Rhodin A., Hartman H.,
Jonsson P., Eriksson K.
<Astron. Astrophys. 598, A100 (2017)>
=2017A&A...598A.100J 2017A&A...598A.100J (SIMBAD/NED BibCode)
ADC_Keywords: Stars, giant ; Abundances ; Spectroscopy
Keywords: solar neighborhood - Galaxy: evolution - stars: abundances
Abstract:
The Galactic bulge is an intriguing and significant part of our
Galaxy, but it is hard to observe because it is both distant and
covered by dust in the disk. Therefore, there are not many
high-resolution optical spectra of bulge stars with large wavelength
coverage, whose determined abundances can be compared with nearby,
similarly analyzed stellar samples.
We aim to determine the diagnostically important alpha elements of a
sample of bulge giants using high-resolution optical spectra with
large wavelength coverage. The abundances found are compared to
similarly derived abundances from similar spectra of similar stars in
the local thin and thick disks.
In this first paper we focus on the solar neighborhood reference
sample. We used spectral synthesis to derive the stellar parameters as
well as the elemental abundances of both the local and bulge samples
of giants. We took special care to benchmark our method of determining
stellar parameters against independent measurements of effective
temperatures from angular diameter measurements and surface gravities
from asteroseismology.
In this first paper we present the method used to determine the
stellar parameters and elemental abundances, evaluate them, and
present the results for our local disk sample of 291 giants.
When comparing our determined spectroscopic temperatures to those
derived from angular diameter measurements, we reproduce these with a
systematic difference of +10K and a standard deviation of 53K. The
spectroscopic gravities reproduce those determined from
asteroseismology with a systematic offset of +0.10dex and a standard
deviation of 0.12dex. When it comes to the abundance trends, our
sample of local disk giants closely follows trends found in other
works analyzing solar neighborhood dwarfs, showing that the much
brighter giant stars are as good abundance probes as the often used
dwarfs.
Description:
Spectroscopic stellar parameters and oxygen, magnesium, calcium, and
titanium abundances for 291 local disk giants are presented. Spectra
from observations with the spectrometer FIES at NOT, and from archives
(FIES and PolarBase) are used. The FIES spectra have R=67000 and the
ones from PolarBase have R=67000. In general most stars are very
bright and have S/N around 100.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 102 291 Basic data for the observed giants
tablea3.dat 76 291 Stellar parameters and abundances for
observed giants
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See also:
J/A+A/543/A160 : Normalized spectra of 82 Kepler red giants (Thygesen+, 2012)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Name Name (HIP, KIC or TYC)
16- 38 A23 --- AName Alternative name
40- 41 I2 h RAh Right ascension (J2000)
43- 44 I2 min RAm Right ascension (J2000)
46- 53 F8.5 s RAs Right ascension (J2000)
55 A1 --- DE- Declination sign (J2000)
56- 57 I2 deg DEd Declination (J2000)
59- 60 I2 arcmin DEm Declination (J2000)
62- 68 F7.4 arcsec DEs Declination (J2000)
70- 74 F5.2 --- Vmag V magnitude
76- 82 F7.2 km/s RV Radial velocity
84- 86 I3 --- S/N Signal-to-noise ratio (1)
88-102 A15 --- Source Source of spectrum (2)
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Note (1): As measured by http://www.stecf.org/software/ASTROsoft/DER_SNR
Note (2): Thygesen+2012 for Thygesen et al., 2012, Cat. J/A+A/543/160.
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Name Name (HIP, KIC or TYC)
17- 20 I4 K Teffr ? Reference effective temperature (1)
22- 23 I2 K e_Teffr ? Uncertaity in reference Teff (1)
25- 28 I4 K Teff Effective temperature
30- 34 F5.3 [cm/s2] loggr ? Reference surface gravity (2)
36- 40 F5.3 [cm/s2] e_loggr ? Uncertainty in reference logg (2)
42- 45 F4.2 [cm/s2] logg Surface gravity
47- 51 F5.2 [-] [Fe/H] Relative iron abundance
53- 56 F4.2 km/s Vmic Microturbulence velocity
58- 61 F4.2 --- A(O) ? Oxygen abundance
63- 66 F4.2 --- A(Mg) Magnesium abundance
68- 71 F4.2 --- A(Ca) Calcium abundance
73- 76 F4.2 --- A(Ti) Titanium abundance
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Note (1): Mozurkewich et al. (2003AJ....126.2502M 2003AJ....126.2502M)
Note (2): Huber et al. (2014ApJS..211....2H 2014ApJS..211....2H)
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Acknowledgements:
Henrik Jonsson, henrikj(at)astro.lu.se
History:
* 08-Feb-2017: on-line version
* 26-Mar-2019: in tablea1.dat, position of HIP105502 corrected
(End) Henrik Jonsson [IAC, Spain], Patricia Vannier [CDS] 30-Nov-2016