J/A+A/622/A191 885 globular cluster giants abundances (Masseron+, 2019)
Homogeneous analysis of globular clusters from the APOGEE survey with the
BACCHUS code. I. The northern clusters.
Masseron T., Garcia-Hernandez D.A., Meszaros S., Zamora O., Dell'Agli F.,
Allende Prieto C., Edvardsson B., Shetrone M., Plez B.,
Fernandez-Trincado J.G., Cunha K., Jonsson H., Geisler D., Beers T.C.,
Cohen R.E.
<Astron. Astrophys. 622, A191 (2019)>
=2019A&A...622A.191M 2019A&A...622A.191M (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Abundances
Keywords: stars: abundances - globular clusters: general
Abstract:
We seek to provide abundances of a large set of light and
neutron-capture elements homogeneously analyzed that cover a wide
range of metallicity to constrain globular cluster (GC) formation and
evolution models.
We analyzed a large sample of 885 GCs giants from the SDSS∼IV-Apache
Point Observatory Galactic Evolution Experiment (APOGEE) survey. We
used the Cannon results to separate the red giant branch and
asymptotic giant branch stars, not only allowing for a refinement of
surface gravity from isochrones, but also providing an independent
H-band spectroscopic method to distinguish stellar evolutionary status
in clusters. We then used the Brussels Automatic Code for
Characterizing High accUracy Spectra (BACCHUS) to derive metallicity,
microturbulence, macroturbulence, many light-element abundances, and
the neutron-capture elements Nd and Ce for the first time from the
APOGEE GCs data.
Our independent analysis helped us to diagnose issues regarding the
standard analysis of the APOGEE DR14 for low-metallicity GC stars.
Furthermore, while we confirm most of the known correlations and
anticorrelation trends (Na-O, Mg-Al, C-N), we discover that some stars
within our most metal-poor clusters show an extreme Mg depletion and
some Si enhancement. At the same time, these stars show some relative
Al depletion, displaying a turnover in the Mg-Al diagram. These stars
suggest that Al has been partially depleted in their progenitors by
very hot proton-capture nucleosynthetic processes. Furthermore, we
attempted to quantitatively correlate the spread of Al abundances with
the global properties of GCs. We find an anticorrelation of the Al
spread against clusters metallicity and luminosity, but the data do
not allow us to find clear evidence of a dependence of N against
metallicity in the more metal-poor clusters.
Large and homogeneously analyzed samples from ongoing spectroscopic
surveys unveil unseen chemical details for many clusters, including a
turnover in the Mg-Al anticorrelation, thus yielding new constrains
for GCs formation/evolution models.
Description:
We investigated the abundances of ten elements (C, N, O, Mg, Al, Si,
K, and Ca, Ce and Nd), for 885 stars in 10 globular clusters (NGC
7078, NGC 6341, NGC 5024, NGC 5466, NGC 6205, NGC 7089, NGC 5272,
NGC 5904, NGC 6171, and NGC 6838) using Apache Point Observatory
Galactic Evolution Experiment (APOGEE; Majewski et al. 2015, Cat.
J/AJ/149/7) DR14 spectra. We make use of photometry and theoretical
isochrones to constrain the effective temperature (Teff) and surface
gravity log(g) and the stellar evolutionnary status (RGB, HB, or early
AGB). The abundances are derived by line fitting with the automatic
code BACCHUS (Masseron, Merle & Hawkins, 2016ascl.soft05004M),
which uses MARCS model atmospheres andf the APOGEE DR14 atomic and
molecular linelists.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 227 885 Stellar parameters and abundances for the 885
globular clusters stars
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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- 2 A2 --- --- [2M]
3- 18 A16 --- 2MASS Star 2MASS identifier
(HHMMSSss+DDMMSSs, J2000)
20- 24 A5 --- Cluster Cluster name
26- 29 A4 --- Evol Stellar evolutionary status
(RGB, HB or eAGB)
31- 34 I4 K Teff Photometric effective temperature
36- 40 F5.2 [cm/s2] logg Log surface gravity; from isochrones
42- 47 F6.3 [Sun] [Fe/H] ? Log Fe/H abundance
49- 53 F5.3 [Sun] e_[Fe/H] ? Error on log Fe/H
55 A1 --- l_[C/Fe] Upper limit flag on [C/Fe]
56- 62 F7.3 [Sun] [C/Fe] ? Log C/Fe abundance
64- 69 F6.3 [Sun] e_[C/Fe] ? Error on log C/Fe abundance
71 I1 --- o_[C/Fe] Number of lines for log C/Fe abundance
73 A1 --- l_[N/Fe] Upper limit flag on [N/Fe]
74- 80 F7.3 [Sun] [N/Fe] ? Log N/Fe abundance
82- 86 F5.3 [Sun] e_[N/Fe] ? Error on log N/Fe abundance
88- 89 I2 --- o_[N/Fe] Number of lines for log N/Fe abundance
91 A1 --- l_[O/Fe] Upper limit flag on [O/Fe]
92- 98 F7.3 [Sun] [O/Fe] ? Log O/Fe abundance
100-104 F5.3 [Sun] e_[O/Fe] ? Error on log O/Fe abundance
106-107 I2 --- o_[O/Fe] Number of lines for log O/Fe abundance
109 A1 --- l_[Mg/Fe] Upper limit flag on [Mg/Fe]
110-116 F7.3 [Sun] [Mg/Fe] ? Log Mg/Fe abundance
118-122 F5.3 [Sun] e_[Mg/Fe] ? Error on log Mg/Fe abundance
124 I1 --- o_[Mg/Fe] Number of lines for log Mg/Fe abundance
126 A1 --- l_[Al/Fe] Upper limit flag on [Al/Fe]
127-133 F7.3 [Sun] [Al/Fe] ? Log Al/Fe abundance
135-139 F5.3 [Sun] e_[Al/Fe] ? Error on log Al/Fe abundance
141 I1 --- o_[Al/Fe] Number of lines for log Al/Fe abundance
143 A1 --- l_[Si/Fe] Upper limit flag on [Si/Fe]
144-150 F7.3 [Sun] [Si/Fe] ? Log Si/Fe abundance
152-156 F5.3 [Sun] e_[Si/Fe] ? Error on log Si/Fe abundance
158-159 I2 --- o_[Si/Fe] Number of lines for log Si/Fe abundance
161 A1 --- l_[K/Fe] Upper limit flag on [K/Fe]
162-168 F7.3 [Sun] [K/Fe] ? Log K/Fe abundance
170-174 F5.3 [Sun] e_[K/Fe] ? Error on log K/Fe abundance
176 I1 --- o_[K/Fe] Number of lines for log K/Fe abundance
178 A1 --- l_[Ca/Fe] Upper limit flag on [Ca/Fe]
179-185 F7.3 [Sun] [Ca/Fe] ? Log Ca/Fe abundance
187-191 F5.3 [Sun] e_[Ca/Fe] ? Error on log Ca/Fe abundance
193 I1 --- o_[Ca/Fe] Number of lines for log Ca/Fe abundance
195 A1 --- l_[Ce/Fe] Upper limit flag on [Ce/Fe]
196-202 F7.3 [Sun] [Ce/Fe] ? Log Ce/Fe abundance
204-208 F5.3 [Sun] e_[Ce/Fe] ? Error on log Ce/Fe abundance
210 I1 --- o_[Ce/Fe] Number of lines for log Ce/Fe abundance
212 A1 --- l_[Nd/Fe] Upper limit flag on [Nd/Fe]
213-219 F7.3 [Sun] [Nd/Fe] ? Log Nd/Fe abundance
221-225 F5.3 [Sun] e_[Nd/Fe] ? Error on log Nd/Fe abundance
227 I1 --- o_[Nd/Fe] Number of lines for log Nd/Fe abundance
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Acknowledgements:
Thomas Masseron, tmasseron(at)iac.es
(End) Patricia Vannier [CDS] 05-Feb-2019