J/ApJ/797/21 Carbon-enhanced metal-poor stars (Placco+, 2014)
Carbon-enhanced metal-poor star frequencies in the Galaxy: corrections for the
effect of evolutionary status on carbon abundances.
Placco V.M., Frebel A., Beers T.C., Stancliffe R.J.
<Astrophys. J., 797, 21 (2014)>
=2014ApJ...797...21P 2014ApJ...797...21P (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Stars, halo ; Abundances ; Stars, atmospheres ;
Stars, population II
Keywords: Galaxy: halo; stars: abundances; stars: atmospheres
stars: Population II
Abstract:
We revisit the observed frequencies of carbon-enhanced metal-poor
(CEMP) stars as a function of the metallicity in the Galaxy, using
data from the literature with available high-resolution spectroscopy.
Our analysis excludes stars exhibiting clear overabundances of
neutron-capture elements and takes into account the expected depletion
of surface carbon abundance that occurs due to CN processing on the
upper red giant branch. This allows for the recovery of the initial
carbon abundance of these stars, and thus for an accurate assessment
of the frequencies of carbon-enhanced stars. The correction procedure
we develop is based on stellar-evolution models and depends on the
surface gravity, log g, of a given star.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 128 616 Data for literature stars
refs.dat 69 39 References
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See also:
III/272 : RAVE 4th data release (Kordopatis+, 2013)
J/A+A/354/169 : Metal-poor field stars abundances (Gratton+, 2000)
J/ApJ/617/1091 : La and Eu abundances in 85 stars (Simmerer+, 2004)
J/A+A/439/129 : HERES II. Spectroscopic analysis (Barklem+, 2005)
J/AJ/132/85 : Equivalent width of 33 metal-poor RHB (Preston+, 2006)
J/ApJ/652/1585 : Bright metal-poor stars from HES survey (Frebel+, 2006)
J/ApJ/655/492 : Equivalent widths of 26 metal-poor stars (Aoki+, 2007)
J/ApJ/658/1203 : Nitrogen-enhanced metal-poor stars (Johnson+, 2007)
J/ApJ/681/1524 : Detailed abundances for 28 metal-poor stars (Lai+, 2008)
J/ApJ/679/1549 : Metal-poor star CS 17435-00532 spectroscopy (Roederer+, 2008)
J/AJ/139/1051 : Carbon-enhanced metal-poor stars in the Galaxy
(Placco+, 2010)
J/ApJ/711/573 : Detailed abundances in a halo stellar stream
(Roederer+, 2010)
J/A+A/528/A92 : HERES VI. Gal. chemical evolution of Si and C (Zhang+, 2011)
J/AJ/142/188 : Metal-poor stars from the HES using CH G-band (Placco+, 2011)
J/ApJ/742/54 : CASH project II. 14 extremely metal-poor stars
(Hollek+, 2011)
J/MNRAS/418/284 : s-process in low-metallicity stars. II. (Bisterzo+, 2011)
J/A+A/548/A34 : Abundances of Carbon-enhanced metal-poor stars (Allen+, 2012)
J/ApJ/778/56 : Hamburg/ESO Survey extremely metal-poor stars (Cohen+, 2013)
J/ApJ/773/33 : Chemical analysis of the metal-poor subgiant BD+44 493
(Ito+, 2013)
J/A+A/509/A93 : Carbon-enhanced metal-poor stars (Masseron+, 2010)
J/ApJ/762/25 : The most metal-poor stars in HES and SDSS. I. (Norris+, 2013)
J/ApJ/762/26 : Most metal-poor stars. II. 190 Gal. halo stars (Yong+, 2013)
J/ApJ/781/40 : Metal-poor stars from HES survey. II. Spectroscopy
(Placco+, 2014)
J/ApJ/814/121 : CASH project. III. The CEMP star HE0414-0343 (Hollek+, 2015)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Name Stellar identifier
15- 18 I4 K Teff [4000/7200] Effective temperature
20- 23 F4.2 [cm/s2] log(g) [0.1/5] Log of the surface gravity
25- 29 F5.2 solLum log(L) [-1.3/3.77] Log of the luminosity (1)
31- 35 F5.2 [-] [Fe/H] [-5.65/-2] Metallicity
37- 40 A4 --- l_[N/Fe] [≤] Limit flag on [N/Fe]
43- 47 F5.2 [-] [N/Fe] [-1.12/4.23]? Log N/Fe number abundance ratio
49- 53 F5.2 [-] [C/Fe] [-1.19/3.9] Log C/Fe number abundance ratio
55- 59 F5.2 [-] Del[C/Fe] [0/0.77] The [C/Fe] correction for [N/Fe]=0
61- 65 F5.2 [-] [C/Fe]c [-1.18/3.91] Correct [C/Fe]
67- 70 A4 --- l_[Sr/Fe] [≤] Limit flag on [Sr/Fe]
73- 77 F5.2 [-] [Sr/Fe] [-2.14/1.77]? Log Sr/Fe number abundance ratio
79- 82 A4 --- l_[Ba/Fe] [≤] Limit flag on [Ba/Fe]
85- 89 F5.2 [-] [Ba/Fe] [-2.41/3.4]? Log Ba/Fe number abundance ratio
91- 99 A9 --- Class Class (2)
101 I1 --- I/O [0/1]? The I/O rejection flag (3)
103-128 A26 --- Ref Reference (see refs.dat file)
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Note (1): The luminosities are derived from the Aoki et al. (2007, Cat.
J/ApJ/655/492) prescription, using M=0.8MSun.
Note (2): Class, defined as follows:
CEMP = [C/Fe]≥+0.7.
CEMP-no = [C/Fe]≥+0.7 and [Ba/Fe]≤0.0, or a published light-element
enrichment pattern that clearly suggests CEMP-no status.
CEMP-s/rs = [C/Fe]≥+0.7 and [Ba/Fe]≥1.0.
Note (3): I/O rejection flag, defined as follows:
1 = accepted stars ([Ba/Fe]<+0.6, [Ba/Sr]<0.0, and upper limits
for [Ba/Fe]).
0 = stars rejected on the CEMP-star frequency calculations
([Ba/Fe]>+1.0 and [Ba/Sr]>0.0).
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 26 A26 --- Ref Reference
28- 46 A19 --- BibCode Bibcode of the reference
48- 69 A22 --- Com Comment
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History:
From electronic version of the journal
(End) Prepared by [AAS], Marianne Brouty [CDS] 26-Jan-2017