J/A+A/592/A87 Chemical abundances of solar analogues (Adibekyan+, 2016)
Abundance trend with condensation temperature for stars with
different Galactic birth places.
Adibekyan V., Delgado-Mena E., Figueira P., Sousa S.G., Santos N.C.,
Gonzalez Hernandez J.I., Minchev I., Faria J.P., Israelian G.,
Harutyunyan G., Suarez-Andres L., Hakobyan A.A.
<Astron. Astrophys. 592, A87 (2016)>
=2016A&A...592A..87A 2016A&A...592A..87A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Abundances
Keywords: techniques: spectroscopy - stars: abundances - stars: atmospheres -
Galaxy: disk - Galaxy: evolution
Abstract:
During the past decade, several studies reported a correlation between
chemical abundances of stars and condensation temperature (also known
as Tc trend). However, the real astrophysical nature of this
correlation is still debated. The main goal of this work is to explore
the possible dependence of the Tc trend on stellar Galactocentric
distances, Rmean. We used high-quality spectra of about 40 stars
observed with the HARPS and UVES spectrographs to derive precise
stellar parameters, chemical abundances, and stellar ages. A
differential line-by-line analysis was applied to achieve the highest
possible precision in the chemical abundances. We confirm previous
results that [X/Fe] abundance ratios depend on stellar age and that
for a given age, some elements also show a dependence on Rmean. When
using the whole sample of stars, we observe a weak hint that the Tc
trend depends on Rmean. The observed dependence is very complex and
disappears when only stars with similar ages are considered. To
conclude on the possible dependence of the Tc trend on the formation
place of stars, a larger sample of stars with very similar atmospheric
parameters and stellar ages observed at different Galactocentric
distances is needed.
Description:
To understand if the abundance trend observed with the condensation
temperature is a function of Galactocentric distances for a fixed age
of stars, we selected about 40 stars with ages similar to that of the
Sun but with different mean Galactocentric distances from the
Geneva-Copenhagen Survey sample (GCS, Nordstroem et al.,
2004A&A...418..989N 2004A&A...418..989N, Cat. V/117): with the smallest (Rmean∼6.5kpc),
largest (Rmean∼9kpc), and solar (Rmean∼8kpc) Galactocentric
Rmean values.
High-resolution and high signal-to-noise (S/N) spectra for these stars
were obtained by performing new observations with HARPS (22 stars) and
UVES (six stars) ESO spectrographs, and by extracting spectra for 14
stars from the ESO archive.
The file param.dat lists the stellar parameters of the stars.
The file abund.dat lists the derived abundances of the elements for
each star.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
param.dat 48 39 Stellar parameters of the stars
abund.dat 323 39 Abundances for each star and element
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See also:
J/AZh/81/541 : Abundances of 15 solar analogues (Galeev+, 2004)
J/A+A/552/A78 : Solar like stars radial velocities (Zechmeister+, 2013)
J/A+A/562/A92 : Li abundance in solar analogues (Delgado Mena+, 2014)
J/A+A/574/A124 : Spectroscopy of solar twins and analogues (Datson+, 2015)
J/A+A/591/A34 : Chemical abundances of zeta Reticuly (Adibekyan+, 2016)
Byte-by-byte Description of file: param.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Star Star's identifier
10- 13 I4 K Teff Effective Temperature
15- 17 I3 K e_Teff rms uncertainty on Teff
19- 22 F4.2 [cm/s2] logg Surface gravity
24- 27 F4.2 [cm/s2] e_logg Surface gravity
29- 33 F5.2 [Sun] [Fe/H] Metallicity
35- 38 F4.2 [Sun] e_[Fe/H] rms uncertainty on [Fe/H]
40- 43 F4.2 km/s Vtur Turbulence velocity
45- 48 F4.2 km/s e_Vtur rms uncertainty on Turbulence velocity
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Byte-by-byte Description of file: abund.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Star Star's identifier
10- 15 F6.3 [Sun] [CI/H] Abundance [CI/H]
17- 21 F5.3 [Sun] e_[CI/H] rms uncertainty of [CI/H]
23- 28 F6.3 [Sun] [OI/H] Abundance [OI/H]
30- 34 F5.3 [Sun] e_[OI/H] rms uncertainty of [OI/H]
36- 41 F6.3 [Sun] [NaI/H] Abundance [NaI/H]
43- 47 F5.3 [Sun] e_[NaI/H] rms uncertainty of [NaI/H]
49- 54 F6.3 [Sun] [MgI/H] Abundance [MgI/H]
56- 60 F5.3 [Sun] e_[MgI/H] rms uncertainty of [MgI/H]
62- 67 F6.3 [Sun] [AlI/H] Abundance [AlI/H]
69- 73 F5.3 [Sun] e_[AlI/H] rms uncertainty of [AlI/H]
75- 80 F6.3 [Sun] [SiI/H] Abundance [SiI/H]
82- 86 F5.3 [Sun] e_[SiI/H] rms uncertainty of [SiI/H]
88- 93 F6.3 [Sun] [SI/H] Abundance [SI/H]
95- 99 F5.3 [Sun] e_[SI/H] rms uncertainty of [SI/H]
101-106 F6.3 [Sun] [CaI/H] Abundance [CaI/H]
108-112 F5.3 [Sun] e_[CaI/H] rms uncertainty of [CaI/H]
114-119 F6.3 [Sun] [ScII/H] Abundance [ScII/H]
121-125 F5.3 [Sun] e_[ScII/H] rms uncertainty of [ScII/H]
127-132 F6.3 [Sun] [Ti/H] Abundance [Ti/H]
134-138 F5.3 [Sun] e_[Ti/H] rms uncertainty of [Ti/H]
140-145 F6.3 [Sun] [VI/H] Abundance [VI/H]
147-151 F5.3 [Sun] e_[VI/H] rms uncertainty of [VI/H]
153-158 F6.3 [Sun] [CrI/H] Abundance [CrI/H]
160-164 F5.3 [Sun] e_[CrI/H] rms uncertainty of [CrI/H]
166-171 F6.3 [Sun] [MnI/H] Abundance [MnI/H]
173-177 F5.3 [Sun] e_[MnI/H] rms uncertainty of [MnI/H]
179-184 F6.3 [Sun] [FeI/H] Abundance [FeI/H]
186-190 F5.3 [Sun] e_[FeI/H] rms uncertainty of [FeI/H]
192-197 F6.3 [Sun] [CoI/H] Abundance [CoI/H]
199-203 F5.3 [Sun] e_[CoI/H] rms uncertainty of [CoI/H]
205-210 F6.3 [Sun] [NiI/H] Abundance [NiI/H]
212-216 F5.3 [Sun] e_[NiI/H] rms uncertainty of [NiI/H]
218-223 F6.3 [Sun] [CuI/H] Abundance [CuI/H]
225-229 F5.3 [Sun] e_[CuI/H] rms uncertainty of [CuI/H]
231-236 F6.3 [Sun] [ZnI/H] Abundance [ZnI/H]
238-242 F5.3 [Sun] e_[ZnI/H] rms uncertainty of [ZnI/H]
244-249 F6.3 [Sun] [SrI/H] ? Abundance [SrI/H]
252-256 F5.3 [Sun] e_[SrI/H] ? rms uncertainty of [SrI/H]
258-263 F6.3 [Sun] [YII/H] Abundance [YII/H]
265-269 F5.3 [Sun] e_[YII/H] rms uncertainty of [YII/H]
271-276 F6.3 [Sun] [ZrII/H] Abundance [ZrII/H]
278-282 F5.3 [Sun] e_[ZrII/H] rms uncertainty of [ZrII/H]
284-289 F6.3 [Sun] [BaII/H] Abundance [BaII/H]
291-295 F5.3 [Sun] e_[BaII/H] rms uncertainty of [BaII/H]
297-302 F6.3 [Sun] [CeII/H] ? Abundance [CeII/H]
305-309 F5.3 [Sun] e_[CeII/H] ? rms uncertainty of [CeII/H]
311-316 F6.3 [Sun] [NdII/H] ? Abundance [NdII/H]
319-323 F5.3 [Sun] e_[NdII/H] ? rms uncertainty of [NdII/H]
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Acknowledgements:
Vardan Adibekyan, Vardan.Adibekyan(at)astro.up.pt
(End) Vardan Adibekyan [IA], Patricia Vannier [CDS] 16-Jun-2016