J/MNRAS/474/2580 Temporal evolution of neutron-capture elements (Spina+, 2018)
The temporal evolution of neutron-capture elements in the Galactic discs.
Spina L., Melendez J., Karakas A.I., dos Santos L., Bedell M., Asplund M.,
Ramirez I., Yong D., Alves-Brito A., Bean J.L., Dreizler S.
<Mon. Not. R. Astron. Soc., 474, 2580-2593 (2018)>
=2018MNRAS.474.2580S 2018MNRAS.474.2580S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, G-type ; Abundances
Keywords: stars: abundances - Galaxy: abundances - Galaxy: disc -
Galaxy: evolution
Abstract:
Important insights into the formation and evolution of the Galactic
disc(s) are contained in the chemical compositions of stars. We
analysed high-resolution and high signal-to-noise HARPS spectra of 79
solar twin stars in order to obtain precise determinations of their
atmospheric parameters, ages (σ∼0.4Gyr) and chemical abundances
(σ<0.01dex) of 12 neutron-capture elements (Sr, Y, Zr, Ba, La,
Ce, Pr, Nd, Sm, Eu, Gd and Dy).
This valuable data set allows us to study the [X/Fe]-age relations
over a time interval of ∼10Gyr and among stars belonging to the thin
and thick discs. These relations show that (i) the s-process has been
the main channel of nucleosynthesis of n-capture elements during the
evolution of the thin disc; (ii) the thick disc is rich in r-process
elements which suggests that its formation has been rapid and
intensive. In addition, the heavy (Ba, La, Ce) and light (Sr, Y, Zr)
s-process elements revealed details on the dependence between the
yields of AGB stars and the stellar mass or metallicity. Finally, we
confirmed that both [Y/Mg] and [Y/Al] ratios can be employed as
stellar clocks, allowing ages of solar twin stars to be estimated with
an average precision of ∼0.5Gyr.
Description:
Spectroscopic parameters and abundances for the 79 solar twin stars
analysed in this paper.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 86 79 The list of the 79 solar twins stars analysed
in this paper
table2.dat 83 79 Atmospheric parameters determined through our
analysis
table3.dat 191 79 Chemical abundances of the n-capture elements
determined for the sample of 79 solar twin stars
table4.dat 105 79 Stellar ages and masses determined for the
sample of 79 solar twins
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See also:
J/A+A/508/L17 : Abundances in solar analogs (Ramirez+, 2009)
J/ApJ/790/L23 : Solar analogs & twins rotation by Kepler (do Nascimento+ 2014)
J/A+A/574/A124 : Spectroscopy of solar twins and analogues (Datson+, 2015)
J/A+A/587/A131 : Solar twins in the ELODIE archive (Mahdi+, 2016)
J/A+A/592/A156 : The Solar Twin Planet Search. IV. (dos Santos+, 2016)
J/ApJ/839/94 : Abundances of solar twins from Keck/HIRES (Bedell+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP HIP identification number
8- 13 A6 --- HD HD name
15- 16 I2 h RAh Right ascension (J2000.0)
18- 19 I2 min RAm Right ascension (J2000.0)
21- 26 F6.3 s RAs Right ascension (J2000.0)
28 A1 --- DE- Declination sign (J2000.0)
29- 30 I2 deg DEd Declination (J2000.0)
32- 33 I2 arcmin DEm Declination (J2000.0)
35- 39 F5.2 arcsec DEs Declination (J2000.0)
41- 45 F5.3 mag Vmag V magnitude (Johnson)
47- 51 F5.3 mag e_Vmag Error V magnitude (Johnson)
53- 57 F5.2 mas plx Parallax
59- 62 F4.2 mas e_plx Error parallax
64- 72 A9 --- r_plx Reference parallax
74- 86 A13 --- Bin Binarity
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [HIP]
4- 9 I6 --- HIP HIP identification number
11- 12 I2 h RAh Right ascension (J2000.0)
14- 15 I2 min RAm Right ascension (J2000.0)
17- 22 F6.3 s RAs Right ascension (J2000.0)
24 A1 --- DE- Declination sign (J2000.0)
25- 26 I2 deg DEd Declination (J2000.0)
28- 29 I2 arcmin DEm Declination (J2000.0)
31- 35 F5.2 arcsec DEs Declination (J2000.0)
37- 40 I4 pix-1 SNR Signal-to-noise ratio
42- 45 I4 K Teff Effective temperature
47- 48 I2 K e_Teff Error of effective temperature
50- 54 F5.3 [cm/s2] logg Surface gravity
56- 60 F5.3 [cm/s2] e_logg Error of Surface gravity
62- 67 F6.3 --- [Fe/H] Iron abundance
69- 73 F5.3 --- e_[Fe/H] Error of iron abundance
75- 78 F4.2 km/s Xi Microturbulence
80- 83 F4.2 km/s e_Xi Error of microturbulence
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [HIP]
4- 9 I6 --- HIP HIP identification number
11- 12 I2 h RAh Right ascension (J2000.0)
14- 15 I2 min RAm Right ascension (J2000.0)
17- 22 F6.3 s RAs Right ascension (J2000.0)
24 A1 --- DE- Declination sign (J2000.0)
25- 26 I2 deg DEd Declination (J2000.0)
28- 29 I2 arcmin DEm Declination (J2000.0)
31- 35 F5.2 arcsec DEs Declination (J2000.0)
37- 42 F6.3 --- [SrI/H] SrI abundance
44- 48 F5.3 --- e_[SrI/H] Error on [SrI/H]
50- 55 F6.3 --- [YII/H] YII abundance
57- 61 F5.3 --- e_[YII/H] Error on [YII/H]
63- 68 F6.3 --- [ZrII/H] ZrII abundance
70- 74 F5.3 --- e_[ZrII/H] Error on [ZrII/H]
76- 81 F6.3 --- [BaII/H] BaII abundance
83- 87 F5.3 --- e_[BaII/H] Error on [BaII/H]
89- 94 F6.3 --- [LaII/H] LaII abundance
96-100 F5.3 --- e_[LaII/H] Error on [LaII/H]
102-107 F6.3 --- [CeII/H] CeII abundance
109-113 F5.3 --- e_[CeII/H] Error on [CeII/H]
115-120 F6.3 --- [PrII/H] PrII abundance
122-126 F5.3 --- e_[PrII/H] Error on [PrII/H]
128-133 F6.3 --- [NdII/H] NdII abundance
135-139 F5.3 --- e_[NdII/H] Error on [NdII/H]
141-146 F6.3 --- [SmII/H] SmII abundance
148-152 F5.3 --- e_[SmII/H] Error on [SmII/H]
154-159 F6.3 --- [EuII/H] EuII abundance
161-165 F5.3 --- e_[EuII/H] Error on [EuII/H]
167-172 F6.3 --- [GdII/H] GdII abundance
174-178 F5.3 --- e_[GdII/H] Error on [GdII/H]
180-185 F6.3 --- [DyII/H] DyII abundance
187-191 F5.3 --- e_[DyII/H] Error on [DyII/H]
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [HIP]
4- 9 I6 --- HIP HIP identification number
11- 12 I2 h RAh Right ascension (J2000.0)
14- 15 I2 min RAm Right ascension (J2000.0)
17- 22 F6.3 s RAs Right ascension (J2000.0)
24 A1 --- DE- Declination sign (J2000.0)
25- 26 I2 deg DEd Declination (J2000.0)
28- 29 I2 arcmin DEm Declination (J2000.0)
31- 35 F5.2 arcsec DEs Declination (J2000.0)
37- 39 F3.1 Gyr Agemp Peak of age probability distribution
41- 43 F3.1 Gyr AgeLL1s Lower limit of the 68% confidence interval
in the age probability distribution
45- 47 F3.1 Gyr AgeUL1s Upper limit of the 68% confidence interval
in the age probability distribution
49- 51 F3.1 Gyr AgeLL2s Lower limit of the 95% confidence interval
in the age probability distribution
53- 55 F3.1 Gyr AgeUL2s Upper limit of the 95% confidence interval
in the age probability distribution
57- 59 F3.1 Gyr Agemean Mean age
61- 63 F3.1 Gyr Agestd Standard deviation
65- 69 F5.3 Msun Massmp Peak of mass probability distribution
71- 75 F5.3 Msun MassLL1s Lower limit of the 68% confidence interval
in the mass probability distribution
77- 81 F5.3 Msun MassUL1s Upper limit of the 68% confidence interval
in the mass probability distribution
83- 87 F5.3 Msun MassLL2s Lower limit of the 95% confidence interval
in the mass probability distribution
89- 93 F5.3 Msun MassUL2s Upper limit of the 95% confidence interval
in the mass probability distribution
95- 99 F5.3 Msun MassMean Mean mass
101-105 F5.3 Msun MassStd Standard deviation
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Acknowledgements:
Lorenzo Spina, lorenzo.spina(at)monash.edu
(End) Lorenzo Spina [Monash University], Patricia Vannier [CDS] 28-Mar-2018