J/A+A/616/A112 Atmospheric param. & abundances of red giants (Smiljanic+, 2018)
Deep secrets of intermediate-mass giants and supergiants.
Models with rotation seem to overestimate mixing effects on the surface
abundances of C, N, and Na.
Smiljanic R., Donati P., Bragaglia A., Lemasle B., Romano D.
<Astron. Astrophys. 616, A112 (2018)>
=2018A&A...616A.112S 2018A&A...616A.112S (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, variable ; Stars, late-type ; Abundances
Keywords: open clusters and associations: general - stars: abundances -
stars: evolution - stars: late-type - stars: variables: Cepheids
Abstract:
Recent observational results have demonstrated an increase in the
surface Na abundance that correlates with stellar mass for red giants
between 2 and 3M☉. This trend supports evolutionary mixing
processes as the explanation for Na overabundances seen in some red
giants. In this same mass range, the surface Al abundance was shown to
be constant.
Our main aim was to extend the investigation of the Na and Al surface
abundances to giants more massive than 3M☉. We sought to
establish accurately whether the Na abundances keep increasing with
stellar mass or a plateau is reached. In addition, we investigated
whether mixing can affect the surface abundance of Al in giants more
massive than 3M☉.
We obtained new high-resolution spectra of 20 giants in the field of
10 open clusters; 17 of these stars were found to be members of 9
clusters. The giants have masses between 2.5M☉ and 5.6M☉.
A model atmosphere analysis was performed and abundances of up to 22
elements were derived using equivalent widths. Additionally,
abundances of C, N, and O were determined using spectrum synthesis.
The abundances of Na and Al were corrected for non-local thermodynamic
equilibrium (non-LTE) effects. Moreover, to extend the mass range of
our sample, we collected from the literature high-quality C, N, O, and
Na abundances of 32 Galactic Cepheids with accurate masses in the
range between 3M☉ and 14M☉.
The surface abundances of C, N, O, Na, and Al were compared to
predictions of stellar evolution models with and without the inclusion
of rotation-induced mixing. The surface abundances of most giants and
Cepheids of the sample can be explained by models without rotation.
For giants above ∼2.5M☉, the Na abundances reach a plateau
level of about [Na/Fe]∼0.20-0.25dex (in non-LTE). This is true
for both Cepheids and giants in open clusters. Regarding Al, the
non-LTE [Al/Fe] ratios are mostly close to solar and suggest that Al
is not affected by the first dredge-up up to ∼5.0M☉. Our
results support previous works that found models with rotation to
overestimate the mixing effects in intermediate-mass stars.
Description:
Atmospheric parameters and abundances are given for a sample of 20 red
giants observed in the field of 10 open clusters. The clusters have
ages between 80Myr and 610Myr. File table5.dat contains the
atmospheric parameters; file table6.dat contains the abundances of C,
N, and O; and file tablea1.dat contains abundances ratios for 28
species of 22 other elements, i.e., [FeI/H], [FeII/H], [AlI/Fe],
[BaII/Fe], [CaI/Fe], [CeII/Fe], [CoI/Fe], [CrI/Fe], [CrII/Fe],
[CuI/Fe], [EuII/Fe], [LaII/Fe], [MgI/Fe], [NaI/Fe], [NiI/Fe],
[ScI/Fe], [ScII/Fe], [SI/Fe], [SiI/Fe], [SiII/Fe], [SrI/Fe], [TiI/Fe],
[TiII/Fe], [VI/Fe], [YII/Fe], [ZnI/Fe], [ZrI/Fe], and [ZrII/Fe].
Parameters and abundances were determined in a model atmosphere
analysis of high-resolution spectra obtained with the FIES instrument
at the Nordic Optical Telescope. Abundances of C, N, and O were
computed using spectrum synthesis. The atmospheric parameters and
remaining abundances were determined using equivalent widths. The
individual Al and Na abundances as given in tablea1.dat have been
corrected for nonlocal thermodynamic equilibrium (non-LTE) effects.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 63 20 List of studied stars
table5.dat 67 20 Atmospheric parameters
table6.dat 45 20 Abundances of C, N, and O
tablea1.dat 407 20 Abundances of other elements
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Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Star Identifier of the star (1)
18- 19 I2 h RAh Right ascension (J2000)
21- 22 I2 min RAm Right ascension (J2000)
24- 28 F5.2 s RAs Right ascension (J2000)
30 A1 --- DE- Declination sign (J2000)
31- 32 I2 deg DEd Declination (J2000)
34- 35 I2 arcmin DEm Declination (J2000)
37- 41 F5.2 arcsec DEs Declination (J2000)
45- 63 A19 --- SName Simbad name
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Note (1): The identifier is composed of the cluster name followed by the star
number. References for the numbering systems:
Collinder 421: 2007A&A...467.1065M 2007A&A...467.1065M
NGC 436: 1994AJ....107.1079P 1994AJ....107.1079P
NGC 1342: 1961PUSNO..17..343H 1961PUSNO..17..343H
NGC 1528: 2006AJ....132.1669S 2006AJ....132.1669S
NGC 1662: 1961PUSNO..17..343H 1961PUSNO..17..343H
NGC 2099: P. Donati (unpublished); Stars 1898 and 2520 are stars 24
and 20 in the numbering system of 2001AJ....122.3239K 2001AJ....122.3239K
NGC 2281: 1959AJ.....64..170V 1959AJ.....64..170V
NGC 6709: numbers 208 and 1998 in the system adopted within WEBDA (the
origin of which is not clear).
Stock 2: 1967ApJ...147..988K 1967ApJ...147..988K
Trumpler 2: 1961PUSNO..17..343H 1961PUSNO..17..343H
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Star Identifier of the star
15- 18 I4 K Teff Effective temperature
22- 24 I3 K e_Teff Error of the Teff measurement
28- 31 F4.2 [cm/s2] logg Logarithm of the surface gravity
35- 38 F4.2 [cm/s2] e_logg Error of the logg measurement
42- 46 F5.2 [Sun] [Fe/H] Metallicity (1)
50- 53 F4.2 [Sun] e_[Fe/H] Error of the [Fe/H] measurement
57- 60 F4.2 km/s Xi Microturbulence
64- 67 F4.2 km/s e_Xi Error of the Xi measurement
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Note (1): For the solar reference iron abundance, the value A(Fe)=7.45 from
Grevesse et al. (2007SSRv..130..105G 2007SSRv..130..105G) is adopted.
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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- 13 A13 --- Star Identifier of the star
16- 20 F5.2 [Sun] [C/Fe] ? Abundance ratio of carbon (1)
24 I1 --- f_[C/Fe] [0/1]? Quality flag of [C/Fe] (2)
27- 30 F4.2 [Sun] [N/Fe] ? Abundance ratio of nitrogen (1)
34 I1 --- f_[N/Fe] [0/1]? Quality flag of [N/Fe] (2)
37- 41 F5.2 [Sun] [O/Fe] ? Abundance ratio of oxygen (1)
45 I1 --- f_[O/Fe] [0/1]? Quality flag of [O/Fe] (2)
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Note (1): For the solar reference abundances we adopted A(C)=8.43, A(N)=7.83,
and A(O)=8.69, from Asplund et al. (2009ARA&A..47..481A 2009ARA&A..47..481A).
Note (2): flags as follows:
0 = fit of good quality
1 = uncertain abundance and/or a good fit was not possible
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Star Identifier of the star
16- 20 F5.2 [Sun] [FeI/H] ? Abundance of FeI (1)
22- 25 F4.2 [Sun] s_[FeI/H] ? Dispersion of [FeI/H]
27- 29 I3 --- o_[FeI/H] ? Number of lines used for [FeI/H]
31- 35 F5.2 [Sun] [FeII/H] ? Abundance of FeII (1)
37- 40 F4.2 [Sun] s_[FeII/H] ? Dispersion of [FeII/H]
42- 43 I2 --- o_[FeII/H] ? Number of lines used for [FeII/H]
45- 49 F5.2 [Sun] [AlI/Fe] ? Abundance of AlI (1)
51- 54 F4.2 [Sun] s_[AlI/Fe] ? Dispersion of [AlI/Fe]
56- 57 I2 --- o_[AlI/Fe] ? Number of lines used for [AlI/Fe]
59- 63 F5.2 [Sun] [BaII/Fe] ? Abundance of BaII (1)
65- 68 F4.2 [Sun] s_[BaII/Fe] ? Dispersion of [BaII/Fe]
70- 71 I2 --- o_[BaII/Fe] ? Number of lines used for [BaII/Fe]
73- 77 F5.2 [Sun] [CaI/Fe] ? Abundance of CaI (1)
79- 82 F4.2 [Sun] s_[CaI/Fe] ? Dispersion of [CaI/Fe]
84- 85 I2 --- o_[CaI/Fe] ? Number of lines used for [CaI/Fe]
87- 91 F5.2 [Sun] [CeII/Fe] ? Abundance of CeII (1)
93- 96 F4.2 [Sun] s_[CeII/Fe] ? Dispersion of [CeII/Fe]
98- 99 I2 --- o_[CeII/Fe] ? Number of lines used for [CeII/Fe]
101-105 F5.2 [Sun] [CoI/Fe] ? Abundance of CoI (1)
107-110 F4.2 [Sun] s_[CoI/Fe] ? Dispersion of [CoI/Fe]
112-113 I2 --- o_[CoI/Fe] ? Number of lines used for [CoI/Fe]
115-119 F5.2 [Sun] [CrI/Fe] ? Abundance of CrI (1)
121-124 F4.2 [Sun] s_[CrI/Fe] ? Dispersion of [CrI/Fe]
126-127 I2 --- o_[CrI/Fe] ? Number of lines used for [CrI/Fe]
129-133 F5.2 [Sun] [CrII/Fe] ? Abundance of CrII (1)
135-138 F4.2 [Sun] s_[CrII/Fe] ? Dispersion of [CrII/Fe]
140-141 I2 --- o_[CrII/Fe] ? Number of lines used for [CrII/Fe]
143-147 F5.2 [Sun] [CuI/Fe] ? Abundance of CuI (1)
149-152 F4.2 [Sun] s_[CuI/Fe] ? Dispersion of [CuI/Fe]
154-155 I2 --- o_[CuI/Fe] ? Number of lines used for [CuI/Fe]
157-161 F5.2 [Sun] [EuII/Fe] ? Abundance of EuII (1)
163-166 F4.2 [Sun] s_[EuII/Fe] ? Dispersion of [EuII/Fe]
168-169 I2 --- o_[EuII/Fe] ? Number of lines used for [EuII/Fe]
171-175 F5.2 [Sun] [LaII/Fe] ? Abundance of LaII (1)
177-180 F4.2 [Sun] s_[LaII/Fe] ? Dispersion of [LaII/Fe]
182-183 I2 --- o_[LaII/Fe] ? Number of lines used for [LaII/Fe]
185-189 F5.2 [Sun] [MgI/Fe] ? Abundance of MgI (1)
191-194 F4.2 [Sun] s_[MgI/Fe] ? Dispersion of [MgI/Fe]
196-197 I2 --- o_[MgI/Fe] ? Number of lines used for [MgI/Fe]
199-203 F5.2 [Sun] [NaI/Fe] ? Abundance of NaI (1)
205-208 F4.2 [Sun] s_[NaI/Fe] ? Dispersion of [NaI/Fe]
210-211 I2 --- o_[NaI/Fe] ? Number of lines used for [NaI/Fe]
213-217 F5.2 [Sun] [NiI/Fe] ? Abundance of NiI (1)
219-222 F4.2 [Sun] s_[NiI/Fe] ? Dispersion of [NiI/Fe]
224-225 I2 --- o_[NiI/Fe] ? Number of lines used for [NiI/Fe]
227-231 F5.2 [Sun] [ScI/Fe] ? Abundance of ScI (1)
233-236 F4.2 [Sun] s_[ScI/Fe] ? Dispersion of [ScI/Fe]
238-239 I2 --- o_[ScI/Fe] ? Number of lines used for [ScI/Fe]
241-245 F5.2 [Sun] [ScII/Fe] ? Abundance of ScII (1)
247-250 F4.2 [Sun] s_[ScII/Fe] ? Dispersion of [ScII/Fe]
252-253 I2 --- o_[ScII/Fe] ? Number of lines used for [ScII/Fe]
255-259 F5.2 [Sun] [SI/Fe] ? Abundance of SI (1)
261-264 F4.2 [Sun] s_[SI/Fe] ? Dispersion of [SI/Fe]
266-267 I2 --- o_[SI/Fe] ? Number of lines used for [SI/Fe]
269-273 F5.2 [Sun] [SiI/Fe] ? Abundance of SiI (1)
275-278 F4.2 [Sun] s_[SiI/Fe] ? Dispersion of [SiI/Fe]
280-281 I2 --- o_[SiI/Fe] ? Number of lines used for [SiI/Fe]
283-287 F5.2 [Sun] [SiII/Fe] ? Abundance of SiII (1)
289-292 F4.2 [Sun] s_[SiII/Fe] ? Dispersion of [SiII/Fe]
294-295 I2 --- o_[SiII/Fe] ? Number of lines used for [SiII/Fe]
297-301 F5.2 [Sun] [SrI/Fe] ? Abundance of SrI (1)
303-306 F4.2 [Sun] s_[SrI/Fe] ? Dispersion of [SrI/Fe]
308-309 I2 --- o_[SrI/Fe] ? Number of lines used for [SrI/Fe]
311-315 F5.2 [Sun] [TiI/Fe] ? Abundance of TiI (1)
317-320 F4.2 [Sun] s_[TiI/Fe] ? Dispersion of [TiI/Fe]
322-323 I2 --- o_[TiI/Fe] ? Number of lines used for [TiI/Fe]
325-329 F5.2 [Sun] [TiII/Fe] ? Abundance of TiII (1)
331-334 F4.2 [Sun] s_[TiII/Fe] ? Dispersion of [TiII/Fe]
336-337 I2 --- o_[TiII/Fe] ? Number of lines used for [TiII/Fe]
339-343 F5.2 [Sun] [VI/Fe] ? Abundance of VI (1)
345-348 F4.2 [Sun] s_[VI/Fe] ? Dispersion of [VI/Fe]
350-351 I2 --- o_[VI/Fe] ? Number of lines used for [VI/Fe]
353-357 F5.2 [Sun] [YII/Fe] ? Abundance of YII (1)
359-362 F4.2 [Sun] s_[YII/Fe] ? Dispersion of [YII/Fe]
364-365 I2 --- o_[YII/Fe] ? Number of lines used for [YII/Fe]
367-371 F5.2 [Sun] [ZnI/Fe] ? Abundance of ZnI (1)
373-376 F4.2 [Sun] s_[ZnI/Fe] ? Dispersion of [ZnI/Fe]
378-379 I2 --- o_[ZnI/Fe] ? Number of lines used for [ZnI/Fe]
381-385 F5.2 [Sun] [ZrI/Fe] ? Abundance of ZrI (1)
387-390 F4.2 [Sun] s_[ZrI/Fe] ? Dispersion of [ZrI/Fe]
392-393 I2 --- o_[ZrI/Fe] ? Number of lines used for [ZrI/Fe]
395-399 F5.2 [Sun] [ZrII/Fe] ? Abundance of ZrII (1)
401-404 F4.2 [Sun] s_[ZrII/Fe] ? Dispersion of [ZrII/Fe]
406-407 I2 --- o_[ZrII/Fe] ? Number of lines used for [ZrII/Fe]
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Note (1): Solar reference abundances are those from Grevesse et al.
(2007SSRv..130..105G 2007SSRv..130..105G).
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Acknowledgements:
Rodolfo Smiljanic, rsmiljanic(at)camk.edu.pl
(End) Rodolfo Smiljanic [CAMK, Poland], Patricia Vannier [CDS] 09-May-2018