J/A+A/601/A112 GES iDR4 Mg-Al anticorrelation in GCs (Pancino+, 2017)
The Gaia-ESO Survey. Mg-Al anti-correlation in iDR4 globular clusters.
Pancino E., Romano D., Tang B., Tautvaisiene G., Casey A.R., Gruyters P.,
Geisler D., San Roman I., Randich S., Alfaro E.J., Bragaglia A.,
Flaccomio E., Korn A.J., Recio-Blanco A., Smiljanic R., Carraro G.,
Bayo A., Costado M.T., Damiani F., Jofre P., Lardo C., de Laverny P.,
Monaco L., Morbidelli L., Sbordone L., Sousa S.G., Villanova S.
<Astron. Astrophys. 601, A112 (2017)>
=2017A&A...601A.112P 2017A&A...601A.112P (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Clusters, globular ; Abundances ; Effective temperatures
Keywords: surveys - stars: abundances - globular clusters: general -
globular clusters: individual: NGC 5927
Abstract:
We use Gaia-ESO Survey iDR4 data to explore the Mg-Al anti-correlation
in globular clusters, that were observed as calibrators, as a
demonstration of the quality of Gaia-ESO Survey data and analysis. The
results compare well with the available literature, within 0.1~[-] or
less, after a small (compared to the Minternal spreads) offset between
the UVES and the GIRAFFE data of 0.10-0.15dex was taken into account.
In particular, we present for the first time data for NGC 5927, one of
the most metal-rich globular clusters studied in the literature so far
with [Fe/H]=-0.49dex, that was included to connect with the open
cluster regime in the Gaia-ESO Survey internal calibration. The extent
and shape of the Mg-Al anti-correlation provide strong constraints on
the multiple population phenomenon in globular clusters. In
particular, we studied the dependency of the Mg-Al anti-correlation
extension with metallicity, present-day mass, and age of the clusters,
using GES data in combination with a large set of homogenized
literature measurements. We find a dependency with both metallicity
and mass, that is evident when fitting for the two parameters
simultaneously, but no significant dependency with age. We confirm
that the Mg-Al anti-correlation is not seen in all clusters, but
disappears for the less massive or most metal-rich ones. We also use
our dataset to see whether a normal anti-correlation would explain the
low [Mg/α] observed in some extragalactic globular clusters,
but find that none of the clusters in our sample can reproduce it, and
more extreme chemical compositions (like the one of NGC 2419) would be
required. We conclude that GES iDR4 data already meet the requirements
set by the main survey goals, and can be used to study in detail
globular clusters even if the analysis procedures were not
specifically designed for them.
Description:
List of globular clusters analyzed in this paper, with basic
properties. List of the 510 stars that were selected from GES iDR4 as
probable members and analyzed in this paper.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 66 9 Globular clusters list with basic properties
table2.dat 92 510 Member stars with parameters and abundances
(corrected version)
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See also:
J/A+A/598/A5 : Gaia-ESO Survey iDR4 calibrators (Pancino+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- NGC NGC cluster identification
8- 13 A6 --- AName Cluster alternate name
15- 19 F5.2 [-] [Fe/H]H Cluster metallicity from Harris,
1996AJ....112.1487H 1996AJ....112.1487H, Cat. VII/195
21- 26 F6.1 km/s RV Cluster radial velocity from Harris,
1996AJ....112.1487H 1996AJ....112.1487H, Cat. VII/195
29- 32 F4.2 [Msun] logM Cluster logarithmic mass
34- 37 F4.2 [Msun] e_logM Error on cluster mass
39 A1 --- r_logM [a/b] Reference for cluster mass (1)
42- 46 F5.2 [-] [Fe/H]G Cluster metallicity from Gaia-ESO survey
48- 51 F4.2 [-] e_[Fe/H]G Error on cluster metallicity
53- 58 F6.1 km/s RVG Radial velocity from Gaia-ESO survey
60- 62 F3.1 km/s e_RVG Error on radial velocity
64- 66 I3 --- Nstar Number of member stars analyzed
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Note (1): The present-day mass is from:
a = McLaughlin & van der Marel (2005, Cat. J/ApJS/161.304)
b = Mandushev et al. (1991A&A...252...94M 1991A&A...252...94M)
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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- 16 A16 --- GES GES star ID based on sexagesimal coordinates,
HHMMSSss+DDMMSSs
18- 24 A7 --- NGC NGC cluster of which the star is member
26- 29 I4 --- Teff Effective temperature
31- 33 I3 --- e_Teff Error on the effective temperature
35- 37 F3.1 --- logg Logarithm of surface gravity in cgs units
39- 41 F3.1 --- e_logg Error on surface gravity
43- 47 F5.2 --- [Fe/H] Metallicity based on iron abundance
49- 52 F4.2 --- e_[Fe/H] Error on metallicity
54- 57 F4.2 --- logAO ? O abundance
59- 62 F4.2 --- e_logAO ? Error on O abundance
64- 67 F4.2 --- logANa ? Na abundance
69- 72 F4.2 --- e_logANa ? Error on Na abundance
74- 77 F4.2 --- logAMg ? Mg abundance
79- 82 F4.2 --- e_logAMg ? Error on Mg abundance
84- 87 F4.2 --- logAAl ? Al abundance
89- 92 F4.2 --- e_logAAl ? Error on Al abundance
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Acknowledgements:
Elena Pancino, pancino(at)arcetri.inaf.it
History:
* 16-May-2017: on-line version
* 31-May-2019: corrected table 2 with O and Na abundances added (from author)
(End) Elena Pancino [INAF-OAA, ASDC], Patricia Vannier [CDS] 31-May-2019