J/A+A/662/A75 CaII spectroscopy of SMC red giants. V. (Parisi+, 2022)
Ca II triplet spectroscopy of Small Magellanic Cloud red giants.
V. Abundances and velocities for 12 massive clusters.
Parisi M.C., Gramajo L.V., Geisler D., Dias B., Claria J.J., Da Costa G.,
Grebel E.K.
<Astron. Astrophys. 662, A75 (2022)>
=2022A&A...662A..75P 2022A&A...662A..75P (SIMBAD/NED BibCode)
ADC_Keywords: Magellanic Clouds ; Associations, stellar ; Abundances ;
Radial velocities ; Optical
Keywords: galaxies: star clusters: general - Magellanic Clouds -
stars: abundances
Abstract:
We aim to analyze the chemical evolution of the Small Magellanic Cloud
adding 12 additional clusters to our existing sample having accurate
and homogeneously derived metallicities. We are particularly
interested in seeing if there is any correlation between age and
metallicity for the different structural components to which the
clusters belong, taking into account their positions relative to the
different tidal structures present in the galaxy.
Spectroscopic metallicities of red giant stars are derived from the
measurement of the equivalent width of the near-IR calcium triplet
lines. Cluster membership analysis was carried out using criteria that
include radial velocities, metallicities, proper motions and distance
from the cluster center.
The mean cluster radial velocity and metallicity were determined with
a typical error of 2.1km/s and 0.03dex, respectively. We added this
information to that available in the literature for other clusters
studied with the same method, compiling a final sample of 48 clusters
with metallicities homogeneously determined. Clusters of the final
sample are distributed in an area of 70deg2 and cover an age range
from 0.4 Gyr to 10.5 Gyr. This is the largest sample of
spectroscopically analyzed SMC clusters available to date.
We confirm the large cluster metallicity dispersion (∼0.6dex) at any
given age in the inner region of the SMC. The metallicity distribution
of our new cluster sample shows a lower probability of being bimodal
than suggested in previous studies. The separate chemical analysis of
clusters in the six components (Main Body, Counter-Bridge, West Halo,
Wing/Bridge, Northern Bridge and Southern Bridge) shows that only
clusters belonging to the Northern Bridge appear to trace a V-Shape,
showing a clear inversion of the metallicity gradient in the outer
regions. There is a suggestion of a metallicity gradient in theWest
Halo, similar to that previously found for field stars. It presents,
however, a very large uncertainty. Also, clusters belonging to theWest
Halo,Wing/Bridge and Southern Bridge exhibit a well-defined
age-metallicity relation with relatively little scatter in abundance
at fixed age compared to other regions.
Description:
The observations were carried out in 2005 and 2006 at the VLT at
European Southern Observatory (ESO, Paranal, Chile), under the
programs 075.B-0548 and 073.B-0488 in service mode (PI: Eva Grebel).
We present radial velocities (RVs) and Calcium Triplet metallicities
(CaT) for a large sample of red giant stars in 12 SMC clusters.
Objects:
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RA (2000) DE Designation(s)
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00 48 50 -69 52.2 L38 = Cl Lindsay 38
00 51 39.55 -71 59 56.6 K28 = Cl Kron 28
01 02 06.34 -73 55 22.7 K44 = Cl Kron 44
00 27 45.17 -72 46 52.5 L11 = Cl Lindsay 11
00 47 24 -68 55.2 L32 = Cl Lindsay 32
01 55 33 -77 39.3 L116 = Cl Lindsay 116
00 32 56.26 -73 06 56.6 NGC 152 = Cl Lindsay 15
00 57 48.90 -74 28 00.2 NGC 339 = Cl Lindsay 59
01 02 12.83 -71 36 16.2 NGC 361 = Cl Lindsay 67
01 07 55.95 -71 46 04.5 NGC 411 = Cl Lindsay 82
01 07 59.0 -72 21 20 NGC 416 = Cl Lindsay 83
01 08 17.79 -72 53 02.8 NGC 419 = Cl Lindsay 85
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 92 85 Measured values for member stars
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See also:
J/AJ/138/517 : CaII spectroscopy of SMC red giants (Parisi+, 2009)
J/AJ/139/1168 : CaII spectroscopy of SMC fields stars (Parisi+, 2010)
J/AJ/149/154 : CaII spectroscopy of SMC red giants. III. (Parisi+, 2015)
J/AJ/152/58 : CaII spectroscopy of SMC red giants. IV. (Parisi+, 2016)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Name Cluster name
8- 9 I2 --- ID Cluster member identification number
within the cluster
11- 12 I2 h RAh Right Ascension (J2000)
14- 15 I2 min RAm Right Ascension (J2000)
17- 21 F5.2 s RAs Right Ascension (J2000)
23 A1 --- DE- Declination sign (J2000)
24- 25 I2 deg DEd Declination (J2000)
27- 28 I2 arcmin DEm Declination (J2000)
30- 34 F5.2 arcsec DEs Declination (J2000)
36- 40 F5.1 km/s RV Heliocentric radial velocity
42- 44 F3.1 km/s e_RV The 1σ error in RV
46- 50 F5.2 mag V-VHB ? Brightness difference between star and
cluster's horizontal branch
52- 55 F4.2 0.1nm SigmaW ? Summed Ca II equivalent width (1)
57- 60 F4.2 0.1nm e_SigmaW ? The 1σ error in SigmaW
62- 66 F5.2 --- [Fe/H] ? Metallicity
68- 71 F4.2 --- e_[Fe/H] ? The error in Metallicity
73- 76 F4.2 mas/yr pmRA ? Proper motion in the right ascension
direction
78- 81 F4.2 mas/yr e_pmRA ? Error in pmRA
83- 87 F5.2 mas/yr pmDE ? Proper motion in the declination direction
89- 92 F4.2 mas/yr e_pmDE ? Error in pmDE
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Note (1): Where SigmaW = EW(8498) + EW(8542) + EW(8662).
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Acknowledgements:
Celeste Parisi, cparisi(at)unc.edu.ar
References:
Parisi et al., Paper I 2009AJ....138..517P 2009AJ....138..517P, Cat. J/AJ/138/517
Parisi et al., Paper II 2010AJ....139.1168P 2010AJ....139.1168P, Cat. J/AJ/139/1168
Parisi et al., Paper III 2015AJ....149..154P 2015AJ....149..154P, Cat. J/AJ/149/154
Parisi et al., Paper IV 2016AJ....152...58P 2016AJ....152...58P, Cat. J/AJ/152/58
(End) Patricia Vannier [CDS] 08-Apr-2022