J/AJ/161/183 Chemical abundances in 52 M-giant stars (Maas+, 2021)
The galactic chemical evolution of chlorine.
Maas Z.G., Pilachowski C.A.
<Astron. J., 161, 183-183 (2021)>
=2021AJ....161..183M 2021AJ....161..183M (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way; Stars, giant; Abundances; Effective temperatures;
Stars, masses; Spectra, infrared; Spectra, optical
Keywords: Stellar abundances; Galaxy chemical evolution
Abstract:
We measured 35Cl abundances in 52-M giants with metallicities in the
range -0.5<[Fe/H]<0.12. Abundances and atmospheric parameters were
derived using infrared spectra from CSHELL on the NASA Infrared
Telescope Facility and from optical echelle spectra. We measured Cl
abundances by fitting a H35Cl molecular feature at 3.6985µm with
synthetic spectra. We also measured the abundances of O, Ca, Ti, and
Fe using atomic absorption lines. We find that the [Cl/Fe] ratio for
our stars agrees with chemical evolution models of Cl, and the [Cl/Ca]
ratio is broadly consistent with the solar ratio over our metallicity
range. Both indicate that Cl is primarily made in core-collapse
supernovae with some contributions from Type Ia supernovae. We suggest
that other potential nucleosynthesis processes, such as the
ν-process, are not significant producers of Cl. Finally, we also
find our Cl abundances are consistent with HII and planetary nebular
abundances at a given oxygen abundance, although there is scatter in
the data.
Description:
Our target stars were observed with CSHELL on the 3m NASA Infrared
Telescope Facility (IRTF). The central wavelength for observations was
36980Å to best observe the H35Cl feature at 36985.1Å, and the
total wavelength range is ∼70Å. A slit width of 0.5" was chosen to
achieve a resolution of R∼40000, necessary to resolve the H35Cl
feature from a nearby OH line.
The optical echelle spectra were obtained from two different
facilities. First, we used The ARC Echelle Spectrograph (ARCES) on the
3.5m Astrophysical Research Consortium (ARC) telescope at the Apache
Point Observatory (APO). ARCES covers a spectral range between 3600
and 10000Å with an approximate resolution of R∼30000. ARCES data
were collected primarily for fainter objects (V≳7mag). The brighter
targets in our sample were observed with TOU on the Dharma 50"
Telescope. TOU covers a similar spectra range of 3800Å-9000Å
with a higher spectral resolution at R∼100000.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 24 52 Sample and observation summary
table3.dat 52 52 M giant stellar parameters and abundances
table8.dat 52 52 M Giant fundamental parameters and UVW
velocities
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/A+A/508/355 : Scaled solar tracks and isochrones (Bertelli+, 2009)
J/ApJ/711/619 : α-element abundances in galactic PNe (Milingo+, 2010)
J/MNRAS/427/343 : IR excesses of Hipparcos stars (McDonald+, 2012)
J/ApJ/764/78 : Oxygen abundances in nearby FGK stars (Ramirez+, 2013)
J/A+A/562/A71 : Chemical abund. solar neighbourhood dwarfs (Bensby+, 2014)
J/A+A/629/A128 : Spectra of molecular absorbers (Wallstrom+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Name HD catalog number
8- 12 F5.2 mag Ksmag [-0.32/4] Apparent Ks magnitude
14 I1 --- r_Ksmag Source for Ksmag (1)
16- 18 I3 --- S/N-IR [40/320] Signal-to-Noise Ratio for IR Spectrum
20 I1 --- Inst Source of Echelle Observation (2)
22- 24 I3 --- S/N-opt [20/390] Signal-to-Noise Ratio Optical Spectrum
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Note (1): References as follows:
1 = The 2MASS Extended sources: IPAC/UMass, 2003-2006, VII/233
2 = DIRBE (Hauser+, 1998ApJ...508...25H 1998ApJ...508...25H; Smith+, 2004ApJS...72..387S 2004ApJS...72..387S)
Note (2): Instruments as follows:
1 = The ARC Echelle Spectrograph (ARCES) on Apache Point Observatory
(APO) 3.5m
2 = TOU on 50" Dharma Endowment Foundation Telescope.
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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- 6 I6 --- Name HD catalog number
8- 11 I4 K Teff [3211/3869] Effective temperature
13- 16 F4.2 [cm/s2] logg [0.12/1.33] Logarithm of the surface gravity
18- 21 F4.2 [-] FeI [7/7.7] The FeI abundance
23- 27 F5.2 [Sun] [Fe/H] [-0.5/0.12] [Fe/H] abundance ratio
29- 32 F4.2 km/s Vt [1.57/2.71] Microturbulence
34- 37 F4.2 [-] O [8.26/8.79]? Oxygen abundance
39- 42 F4.2 [-] 35Cl [4.27/5.41] The 35Cl abundance
44- 47 F4.2 [-] Ca [5.59/6.85] The Calcium abundance
49- 52 F4.2 [-] Ti [4.43/5.19] The Titanium abundance
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Name HD catalog number
8- 11 I4 solLum Lum [260/5700] Luminosity
13- 16 I4 solLum e_Lum [80/2090] Mean uncertainty in Lum
18- 20 I3 pc Dist [180/836] Stellar distance (1)
22- 25 F4.2 solMass Mass [1/3] Stellar mass
27- 31 F5.1 km/s U [-92.2/112] U Galactic velocity component
33- 39 F7.2 km/s V [-270/8.5] V Galactic velocity component
41- 46 F6.2 km/s W [-66.9/132] W Galactic velocity component
48- 52 F5.1 --- PRatio [0/124] Thin to thick disk membership
probability ratio
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Note (1): From Bailer-Jones+, 2018, I/347.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 07-Jul-2021