J/A+A/640/A89 56 Galactic bulge red giants Co and Cu abund. (Ernandes+, 2020)
Cobalt and copper abundances in 56 Galactic bulge red giants.
Ernandes H., Barbuy B., Friaca A.C.S., Hill V., Zoccali M., Minniti D.,
Renzini A., Ortolani S.
<Astron. Astrophys., 640, A89 (2020)>
=2020A&A...640A..89E 2020A&A...640A..89E (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way; Stars, giant ; Abundances
Keywords: stars: abundances - Galaxy: bulge - Galaxy: abundances -
nuclear reactions, nucleosynthesis, abundances - stars: late-type
Abstract:
The Milky Way bulge is an important tracer of the early formation and
chemical enrichment of the Galaxy. The abundances of different
iron-peak elements in field bulge stars can give information on the
nucleosynthesis processes that took place in the earliest supernovae.
Cobalt (Z=27) and copper (Z=29) are particularly interesting.
We aim to identify the nucleosynthesis processes responsible for the
formation of the iron-peak elements Co and Cu.
We derived abundances of the iron-peak elements cobalt and copper in
56 bulge giants, 13 of which were red clump stars. High-resolution
spectra were obtained using FLAMES-UVES at the ESO Very Large
Telescope by our group in 2000-2002, which appears to be the highest
quality sample of optical high-resolution data on bulge red giants
obtained in the literature to date. Over the years we have derived the
abundances of C, N, O, Na, Al, Mg; the iron-group elements Mn and Zn;
and neutron-capture elements. In the present work we derive abundances
of the iron-peak elements cobalt and copper. We also compute
chemodynamical evolution models to interpret the observed behaviour of
these elements as a function of iron.
The sample stars show mean values of [Co/Fe]∼0.0 at all metallicities,
and [Cu/Fe]∼0.0 for [Fe/H]≥-0.8 and decreasing towards lower
metallicities with a behaviour of a secondary element.
We conclude that [Co/Fe] varies in lockstep with [Fe/H], which
indicates that it should be produced in the alpha-rich freezeout
mechanism in massive stars. Instead [Cu/Fe] follows the behaviour of a
secondary element towards lower metallicities, indicating its
production in the weak s-process nucleosynthesis in He-burning and
later stages. The chemodynamical models presented here confirm the
behaviour of these two elements (i.e. [Co/Fe] vs. [Fe/H] ∼ constant and
[Cu/Fe] decreasing with decreasing metallicities).
Description:
The present data consist of high-resolution spectra of 43 bulge red
giants, chosen to have one magnitude brighter than the red clump, from
ESO programmes 71.B-0617A and 73.B0074A (PI: A. Renzini) obtained with
the FLAMES-UVES spectrograph at the 8.2m Kueyen Very Large Telescope
at the Paranal Observatory of the European Southern Observatory (ESO).
We derived the abundances of the iron-peak elements Co and Cu in 56
red giants of the Galactic bulge, for which we have previously derived
abundances of C, N, O, Na, Mg, Al, Mn, Zn, and heavy elements.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 94 56 Atmospheric parameters and radial velocities
adopted from Zoccali et al. (2006A&A...457L...1Z 2006A&A...457L...1Z)
and Lecureur et al. (2007A&A...465..799L 2007A&A...465..799L,
Cat. J/A+A/465/799), and resulting Co and Cu
abundances
table3.dat 76 56 LTE abundances of Co and Cu derived in the
present work
table6.dat 84 41 Comparison of stellar parameters and Co and Cu
abundances of the present work with
Johnson et al. (2014AJ....148...67J 2014AJ....148...67J) and
Lomaeva et al. (2019A&A...625A.141L 2019A&A...625A.141L)
tableb1.dat 54 56 NLTE corrections to the derived LTE abundances
of Co
tabled1.dat 76 56 Metallicity [Fe/H] and abundances of C, N, O, Na,
Mg, Al, Mn, Co, Cu for the 56 sample red giants
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See also:
J/A+A/465/799 : Abundances of Galactic Bulge red giants (Lecureur+, 2007)
J/AJ/148/67 : Abundances of 156 bulge red giants (Johnson+, 2014)
J/A+A/625/A141 : Abundances of disk and bulge giants (Lomaeva+, 2019)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Star Star name, [LHZ2007] Star in Simbad
9- 16 A8 --- OGLE OGLE designation
18- 19 I2 h RAh Right ascension (J2000)
21- 22 I2 min RAm Right ascension (J2000)
24- 29 F6.3 s RAs Right ascension (J2000)
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 43 F6.3 arcsec DEs Declination (J2000)
45- 48 I4 K Teff Effective temperature
50- 52 F3.1 [cm/s2] logg Surface gravity
54- 58 F5.2 [-] [Fe/H] Metallicity
60- 62 F3.1 km/s vt Micorturbulent velocity
64- 69 F6.1 km/s vr ? Radial velocity
70- 76 F7.2 km/s vhelio Heliocentric velocity
78- 82 F5.2 [-] [Cu/Fe]LTE ? LTE [Cu/Fe] abundance
84- 88 F5.2 [-] [Co/Fe]LTE ? LTE [Co/Fe] abundance
90- 94 F5.2 [-] [Co/Fe]NLTE Non-LTE [Co/Fe] abundance
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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- 7 A7 --- Star Star name, [LHZ2007] Star in Simbad
8- 12 F5.2 [-] [Fe/H] Abundance, [Fe/H]
14- 18 F5.2 [-] [Cu/Fe]1 ? Abundance, [Cu/Fe], 5105.5374Å
20- 24 F5.2 [-] [Cu/Fe]2 ? Abundance, [Cu/Fe], 5218.1974Å
26- 30 F5.2 [-] [Co/Fe]1 ? Abundance, [Co/Fe], 5212.691Å
31 A1 --- u_[Co/Fe]1 Uncertainty flag on [Co/Fe]1
33- 37 F5.2 [-] [Co/Fe]2 ? Abundance, [Co/Fe], 5280.629Å
39- 43 F5.2 [-] [Co/Fe]3 ? Abundance, [Co/Fe], 5301.047Å
45- 49 F5.2 [-] [Co/Fe]4 ? Abundance, [Co/Fe], 5342.708Å
51- 55 F5.2 [-] [Co/Fe]5 ? Abundance, [Co/Fe], 5454.572Å
56 A1 --- u_[Co/Fe]5 Uncertainty flag on [Co/Fe]5
58- 62 F5.2 [-] [Co/Fe]6 Abundance, [Co/Fe], 5647.234Å
63 A1 --- u_[Co/Fe]6 Uncertainty flag on [Co/Fe]6
65- 69 F5.2 [-] [Co/Fe]7 ? Abundance, [Co/Fe], 6117.000Å
70 A1 --- u_[Co/Fe]7 Uncertainty flag on [Co/Fe]7
72- 76 F5.2 [-] [Co/Fe]8 ? Abundance, [Co/Fe], 6188.996Å
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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- 5 A5 --- Star Star name, [LHZ2007] Star in Simbad
8- 15 A8 --- OGLE OGLE designation
18- 21 I4 K Teff ? Effective temperature, Present work
23- 26 F4.2 [cm/s] logg ? Surface gravity, Present work
28- 32 F5.2 [-] [Fe/H] ? Metallicity, Present work
34- 37 F4.2 km/s vt ? Microturbulent velocity, Present work
39- 43 F5.2 [-] [Co/Fe]LTE ? LTE [Co/Fe] abundance, Present work
45- 49 F5.2 [-] [Co/Fe]NLTE ? Non-LTE [Co/Fe] abundance, Present work
51- 55 F5.2 [-] [Cu/Fe] ? Abundance [Cu/Fe], Present work
57 A1 --- Ref [JL] Reference for second set of values (1)
59- 62 I4 K Teff2 Effective temperature from Ref
64- 67 F4.2 [cm/s2] logg2 Surface gravity from Ref
69- 73 F5.2 [-] [Fe/H]2 Metallicity from Ref
75- 78 F4.2 [-] [Co/Fe]2 Abundance [Co/Fe] from from Ref
80- 84 F5.2 [-] [Cu/Fe]2 ? Abundance [Cu/Fe] from from Ref2
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Note (1): Reference as follows:
J = Johnson et al., 2014AJ....148...67J 2014AJ....148...67J, Cat. J/AJ/148/67
L = Lomaeva et al., 2019A&A...625A.141L 2019A&A...625A.141L. Cat. J/A+A/625/A141
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Star Star name, [LHZ2007] Star in Simbad
8- 12 F5.3 [-] [Co/Fe]1 NLTE corrections to [Co/Fe] 5212.691Å
abundance
14- 18 F5.3 [-] [Co/Fe]2 NLTE corrections to [Co/Fe] 5280.629Å
abundance
20- 24 F5.3 [-] [Co/Fe]3 NLTE corrections to [Co/Fe] 5301.047Å
abundance
26- 30 F5.3 [-] [Co/Fe]4 NLTE corrections to [Co/Fe] 5342.708Å
abundance
32- 36 F5.3 [-] [Co/Fe]5 NLTE corrections to [Co/Fe] 5454.572Å
abundance
38- 42 F5.3 [-] [Co/Fe]6 NLTE corrections to [Co/Fe] 5647.234Å
abundance
44- 48 F5.3 [-] [Co/Fe]7 NLTE corrections to [Co/Fe] 6117.000Å
abundance
50- 54 F5.3 [-] [Co/Fe]8 NLTE corrections to [Co/Fe] 6188.996Å
abundance
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Byte-by-byte Description of file: tabled1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Star Star name, [LHZ2007] Star in Simbad
8- 12 F5.2 [-] [Fe/H] Metallicity
14- 18 F5.2 [-] [C/Fe] ? Abundance [C/Fe]
20- 24 F5.2 [-] [N/Fe] ? Abundance [N/Fe]
26- 30 F5.2 [-] [O/Fe] ? Abundance [O/Fe]
32- 36 F5.2 [-] [Na/Fe] ? Abundance [Na/Fe]
38- 41 F4.2 [-] [Mg/Fe] ? Abundance [Mg/Fe]
43- 46 F4.2 [-] [Al/Fe] ? Abundance [Al/Fe]
48- 52 F5.2 [-] [Mn/Fe] Abundance [Mn/Fe]
54- 58 F5.2 [-] [Cu/Fe] ? Abundance [Cu/Fe]
60- 64 F5.2 [-] [Co/Fe]LTE LTE abundance [Co/Fe]
66- 70 F5.2 [-] [Co/Fe]NLTE NLTE abundance [Co/Fe]
72- 76 F5.2 [-] [Zn/Fe] ? Abundance [Zn/Fe]
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 02-Nov-2020