J/A+A/671/A124 Chemical composition of 206 SMC red giants (Mucciarelli+, 2023)
The chemical DNA of the Magellanic Clouds.
I.The chemical composition of 206 Small Magellanic Cloud red giant stars.
Mucciarelli A., Minelli A., Bellazzini M., Lardo C., Romano D., Origlia L.,
Ferraro F.R.
<Astron. Astrophys. 671, A124 (2023)>
=2023A&A...671A.124M 2023A&A...671A.124M (SIMBAD/NED BibCode)
ADC_Keywords: Magellanic Clouds ; Stars, giant ; Abundances ; Spectroscopy ;
Optical
Keywords: Magellanic Clouds - techniques: spectroscopic - stars: abundances
Abstract:
We present the chemical composition of 206 red giant branch stars
members of the Small Magellanic Cloud (SMC) using optical,
high-resolution spectra collected with the multi-object spectrograph
FLAMES-GIRAFFE at the ESO Very Large Telescope. This sample includes
stars in three fields located in different positions within the parent
galaxy. We analysed the main groups of elements, namely light- (Na),
α- (O, Mg, Si, Ca, Ti), iron-peak (Sc, V, Fe, Ni, Cu) and
s-process elements (Zr, Ba, La). The metallicity distribution of the
sample displays a main peak around [Fe/H]~-1 --- and a weak metal-poor
tail. However, the three fields display [Fe/H] distributions different
with each other, in particular a difference of 0.2 --- is found
between the mean metallicities of the two most internal fields. The
fraction of metal-poor stars increases significantly (from ∼1 to ∼20%)
from the innermost fields to the most external one, likely reflecting
an age gradient in the SMC. Also, we found a hint of possible
chemically/kinematic distinct substructures. The SMC stars have
abundance ratios clearly distinct with respect to the Milky Way stars,
in particular for the elements produced by massive stars (like Na,
α and most iron-peak elements) that have abundance ratios
systematically lower than those measured in our Galaxy. This points
out that the massive stars contributed less to the chemical enrichment
of the SMC with respect to the Milky Way, according to the low star
formation rate expected for this galaxy. Finally, we identified small
systematic differences in the abundances of some elements (Na, Ti, V
and Zr) in the two innermost fields, suggesting that the chemical
enrichment history in the SMC has been not uniform.
Description:
Table 2 includes star name, identification and coordinate from Gaia
Early Data Release 3, heliocentric radial velocity and its
uncertainty, the atmospheric parameters and the abundance of Fe.
Table 3 includes all the used atomic lines with the corresponding
atomic data and references.
Table 5 includes all the chemical abundance ratios. 99.99 stands for
no measured abundance. Upper limits are flagged as 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 113 206 Main information of the observed targets
table3.dat 71 119 Main information of the used atomic lines
table5.dat 216 206 Chemical abundances of the observed targets
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Name Star name (FLD-NNN_NNNNNN)
17- 35 I19 --- GaiaEDR3 Gaia EDR3 identification number
40- 49 F10.7 deg RAdeg Right ascension (ICRS) at Ep=2016.0
53- 63 F11.7 deg DEdeg Declination (ICRS) at Ep=2016.0
70- 74 F5.1 km/s RV Heliocentric radial velocity
78- 80 F3.1 km/s e_RV Uncertainty on radial velocity
83- 86 I4 K Teff Effective temperature
90- 93 F4.2 [cm/s2] logg Surface gravity
96- 98 F3.1 km/s vt Microturbulent velocity
103-107 F5.2 --- [Fe/H] Abundance relative to the Sun for FeI
110-113 F4.2 --- e_[Fe/H] Uncertainty on the abundance for FeI
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 F8.3 10nm lambda Wavelength
13- 14 A2 --- El Chemical element
16- 17 A2 --- Ion Ionization stage
24- 29 F6.3 [-] loggf log of oscillator strength
36- 40 F5.3 eV chi Excitation potential
48- 71 A24 --- r_loggf Reference of the loggf (1)
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Note (1): References as follows:
Biemont et al.(1981) = 1981ApJ...248..867B 1981ApJ...248..867B
Fuhr & Wiese (2006) = J. Phys. Chem. Ref. Data, Vol. 35, 1669
Fuhr et al.(1988) = J. Phys. Chem. Ref. Data, Vol. 17, Cat. VI/72
Lawler et al.(2001) = 2001ApJ...556..452L 2001ApJ...556..452L
Lawler et al.(2013) = 2013ApJS..205...11L 2013ApJS..205...11L
Martin et al.(1988) = J. Phys. Chem. Ref. Data, Vol. 17, Cat. VI/72
Mucciarelli et al.(2017) = 2017A&A...603L...7M 2017A&A...603L...7M, Cat. J/A+A/603/L7
Smith & Raggett (1981) = Journal of Physics B Atomic Molecular
Physics, 14, 4015
Storey & Zeippen(2000) = 2000MNRAS.312..813S 2000MNRAS.312..813S
Wood et al.(2014) = 2014ApJ...787L..16W 2014ApJ...787L..16W
NIST = NIST database, http://physics.nist.gov/PhysRefData
SUN = SUN
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Name Star name (FLD-NNN_NNNNNN)
25- 29 F5.2 --- [Fe/H] Abundance relative to the Sun for FeI
32- 36 F5.2 --- [O/Fe] ?=99.99 Abundance relative to the Sun for OI
38- 42 F5.2 --- e_[O/Fe] ?=99.99 Uncertainty on the abundance for OI
45 A1 --- l_[O/Fe] [0/1] Upper limit for OI (1)
48- 52 F5.2 --- [Na/Fe] ?=99.99 Abundance relative to the Sun for NaI
54- 58 F5.2 --- e_[Na/Fe] ?=99.99 Uncertainty on the abundance for NaI
61 A1 --- l_[Na/Fe] [0/1] Upper limit for NaI (1)
64- 68 F5.2 --- [Mg/Fe] ?=99.99 Abundance relative to the Sun for MgI
70- 74 F5.2 --- e_[Mg/Fe] ?=99.99 Uncertainty on the abundance for MgI
77- 81 F5.2 --- [Si/Fe] ?=99.99 Abundance relative to the Sun for SiI
83- 87 F5.2 --- e_[Si/Fe] ?=99.99 Uncertainty on the abundance for SiI
90 A1 --- l_[Si/Fe] [0/1] Upper limit for SiI (1)
93- 97 F5.2 --- [Ca/Fe] ?=99.99 Abundance relative to the Sun for CaI
99-103 F5.2 --- e_[Ca/Fe] ?=99.99 Uncertainty on the abundance for CaI
106-110 F5.2 --- [Sc/Fe] ?=99.99 Abundance relative to the Sun for ScII
112-116 F5.2 --- e_[Sc/Fe] ?=99.99 Uncertainty on the abundance for ScII
119-123 F5.2 --- [Ti/Fe] ?=99.99 Abundance relative to the Sun for TiI
125-129 F5.2 --- e_[Ti/Fe] ?=99.99 Uncertainty on the abundance for TiI
132-136 F5.2 --- [V/Fe] ?=99.99 Abundance relative to the Sun for VI
138-142 F5.2 --- e_[V/Fe] ?=99.99 Uncertainty on the abundance for VI
145-149 F5.2 --- [Ni/Fe] ?=99.99 Abundance relative to the Sun for NiI
151-155 F5.2 --- e_[Ni/Fe] ?=99.99 Uncertainty on the abundance for NiI
158-162 F5.2 --- [Cu/Fe] ?=99.99 Abundance relative to the Sun for CuI
164-168 F5.2 --- e_[Cu/Fe] ?=99.99 Uncertainty on the abundance for CuI
171 A1 --- l_[Cu/Fe] [0/1] Upper limit for CuI (1)
174-178 F5.2 --- [Zr/Fe] ?=99.99 Abundance relative to the Sun for ZrI
180-184 F5.2 --- e_[Zr/Fe] ?=99.99 Uncertainty on the abundance for ZrI
187 A1 --- l_[Zr/Fe] [0/1] Upper limit for ZrI (1)
190-194 F5.2 --- [Ba/Fe] ?=99.99 Abundance relative to the Sun for BaII
196-200 F5.2 --- e_[Ba/Fe] ?=99.99 Uncertainty on the abundance for BaII
203-207 F5.2 --- [La/Fe] ?=99.99 Abundance relative to the Sun for LaII
209-213 F5.2 --- e_[La/Fe] ?=99.99 Uncertainty on the abundance for LaII
216 A1 --- l_[La/Fe] [0/1] Upper limit for LaII (1)
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Note (1): Upper limits code as follows:
0 = True measure
1 = Upper limit
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Acknowledgements:
Alessio Mucciarelli, alessio.mucciarelli2(at)unibo.it
(End) Patricia Vannier [CDS] 24-Jan-2023