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J/AJ/130/2804       Carbon abundances in metal-poor stars         (Rossi+, 2005)

Estimation of carbon abundances in metal-poor stars. I. Application to the strong G-band stars of Beers, Preston, and Shectman. Rossi S., Beers T.C., Sneden C., Sevastyanenko T., Rhee J., Marsteller B. <Astron. J., 130, 2804-2823 (2005)> =2005AJ....130.2804R
ADC_Keywords: Abundances ; Stars, carbon ; Stars, metal-deficient Keywords: abundances - stars: carbon - stars: Population II - techniques: spectroscopic Abstract: We develop and test a method for the estimation of metallicities ([Fe/H]) and carbon abundance ratios ([C/Fe]) for carbon-enhanced metal-poor (CEMP) stars based on the application of artificial neural networks, regressions, and synthesis models to medium-resolution (1-2Å) spectra and J-K colors. We calibrate this method by comparison with metallicities and carbon abundance determinations for 118 stars with available high-resolution analyses reported in the recent literature. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 65 119 Photometric information for calibration stars table3.dat 78 119 Spectroscopic observations, and adopted abundance and model parameters for calibration stars refs.dat 120 24 References table4.dat 96 119 Estimates of [Fe/H] and [C/Fe] from artificial neural networks, regression, and synthesis for calibration stars table6.dat 65 56 *Photometric information for BPSII "Strong G-Band" stars table7.dat 87 56 *Spectroscopic observations, derived abundances, and model parameters for BPSII "Strong G-Band" stars
Note on table6.dat and table7.dat: BPSII stands for Beers et al., 1992, Cat. J/AJ/103/1987
See also: J/AJ/103/1987 : Stars of very low metal abundance (Beers+ 1992) J/A+A/354/169 : Metal-poor field stars abundances (Gratton+, 2000) J/A+A/356/238 : Atmospheric parameters in metal-poor stars. III. (Carretta+ 2000) J/A+A/375/366 : Carbon stars from the Hamburg/ESO survey (Christlieb+ 2001) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Name Star name 14- 18 F5.2 mag Vmag The V band magnitude 20- 23 F4.2 mag B-V The (B-V) color index 25- 30 F6.3 mag Jmag 2MASS J band magnitude 32- 36 F5.3 mag e_Jmag Uncertainty in Jmag 38- 42 F5.3 mag J-K 2MASS (J-K) color index 44- 48 F5.3 mag e_J-K Uncertainty in J-K 50- 54 F5.3 mag E(B-V) The adopted E(B-V) color excess 56- 59 F4.2 mag (B-V)0 The intrinsic (B-V) color index 61- 65 F5.3 mag (J-K)0 The intrinsic (J-K) color index
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Name Star name 14- 21 A8 --- Tel Telescope(s) used in the observation (G1) 23- 27 F5.2 0.1nm KP The KP line index (G2) 29- 32 F4.2 0.1nm GP The GP line index (G3) 34- 38 F5.2 [Sun] [Fe/H] Adopted [Fe/H] from literature 40- 44 F5.2 [Sun] [C/H] Adopted [C/H] from literature 46- 50 F5.2 [Sun] [C/Fe] Adopted [C/Fe] from literature 52- 60 A9 --- Ref Reference source(s) (detailed in refs.dat) 62- 65 I4 K Teff Model effective temperature (1) 67- 69 F3.1 [cm/s2] log(g) Model log surface gravity (1) 71- 74 F4.1 [Sun] M[Fe/H] Model [Fe/H] (1) 76- 78 F3.1 km/s xi Microturbulence velocity (1)
Note (1): The model parameters listed are those adopted based on the literature sources listed. For consistency of the spectral synthesis modeling with the predicted [C/Fe] for the BPSII "Strong G-Band" stars in Table 7, we used an input microturbulence value of 2.0km/s for estimation of the [C/Fe]S values reported in this table.
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 2 I2 --- Ref Reference number 4- 22 A19 --- Bibcode Bibcode 24- 48 A25 --- Aut Author's name 50-120 A71 --- Comm Comment
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Name Star name 14- 18 F5.2 [Sun] [Fe/H] Adopted [Fe/H] 20- 24 F5.2 [Sun] [Fe/H]A Derived artificial neural network analysis [Fe/H] 26- 30 F5.2 [Sun] res[Fe/H]A Residual in derived [Fe/H]A 32- 36 F5.2 [Sun] [Fe/H]R ? Derived regression analysis [Fe/H] 38- 42 F5.2 [Sun] res[Fe/H]R ? Residual in derived [Fe/H]R 44- 48 F5.2 [Sun] [C/Fe] Adopted external [C/Fe] estimate from the literature 50- 54 F5.2 [Sun] [C/Fe]A Derived analysis [C/Fe] 56- 60 F5.2 [Sun] res[C/Fe] Residual in derived [C/Fe]A 62- 66 F5.2 [Sun] [C/Fe]R Derived regression analysis [C/Fe] 68- 72 F5.2 [Sun] res[C/Fe]R Residual in derived [C/Fe]R 74 I1 --- B-Teff [1/4] Calibration star groupings in effective temperature bin (1) 76 I1 --- B-Fe/H [1/4] Calibration star groupings in [Fe/H] bin (2) 78 I1 --- B-C/Fe [1/4] Calibration star groupings in [C/Fe] bin (3) 80 A1 --- l_[C/Fe]S Limit flag on [C/Fe]S 82- 86 F5.2 [Sun] [C/Fe]S Spectral synthesis estimate of [C/Fe] 87- 88 A2 --- u_[C/Fe]S [ :] Uncertainty flag on [C/Fe]S (4) 90- 94 F5.2 [Sun] res[C/Fe]S ? Residual in [C/Fe]S 96 A1 --- f_Name [X] Indicates star not used in calibration of the ANNs or regression estimates of [C/Fe]
Note (1): Calibration star groupings in Teff bin, defined as follows: 1 = Teff>5500K; 2 = 5000K<Teff≤5500K; 3 = 4500K<Teff≤5000K; 4 = Teff≤4500K. Note (2): Calibration star groupings in [Fe/H] bin, defined as follows: 1 = [Fe/H]>-1.0; 2 = -2.0<[Fe/H]≤-1.0; 3 = -3.0<[Fe/H]≤-2.0; 4 = [Fe/H]≤-3.0. Note (3): Calibration star groupings in [C/Fe] bin, defined as follows: 1 = [C/Fe]>+1.0; 2 = +0.50<[C/Fe]≤+1.0; 3 = 0.0≤[C/Fe]≤+0.5; 4 = [C/Fe]≤0.0. Note (4): Uncertainty flag on [C/Fe]S, defined as follows: : = uncertain; :: = highly uncertain.
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 2 A2 --- --- [CS] 4- 12 A9 --- BPS-CS Star name (BPS CS NNNNN-NNN in Simbad) 14- 18 F5.2 mag Vmag ? The V band magnitude 20- 23 F4.2 mag B-V ? The (B-V) color index 25- 30 F6.3 mag Jmag ? The J band magnitude 32- 36 F5.3 mag e_Jmag ? Uncertainty in Jmag 38- 42 F5.3 mag J-K ? The (J-K) color index 44- 48 F5.3 mag e_J-K ? Uncertainty in J-K 50- 54 F5.3 mag E(B-V) The (B-V) color excess 56- 59 F4.2 mag (B-V)0 ? The intrinsic (B-V) color index 61- 65 F5.3 mag (J-K)0 ? The intrinsic (J-K) color index
Byte-by-byte Description of file: table7.dat
Bytes Format Units Label Explanations
1- 2 A2 --- --- [CS] 4- 12 A9 --- BPS-CS Star name (BPS CS NNNNN-NNN in Simbad) 14- 17 A4 --- Tel Telescope used in the observation (G1) 19- 22 F4.2 --- KP The KP line index (G2) 24- 27 F4.2 --- GP The GP line index (G3) 29- 33 F5.2 [Sun] [Fe/H]A ? Log of the artificial neural network analysis Fe/H abundance estimate 35- 39 F5.2 [Sun] [Fe/H]R ? Log of the regression analysis Fe/H abundance 41- 45 F5.2 [Sun] [C/Fe]A Log of the artificial neural network analysis C/Fe abundance estimate 46- 47 A2 --- u_[C/Fe]A [ :] Uncertainty flag on [C/Fe]A (2) 49- 53 F5.2 [Sun] [C/Fe]R Log of the regression analysis C/Fe abundance 54- 55 A2 --- u_[C/Fe]R [ :] Uncertainty flag on [C/Fe]R (2) 57- 60 I4 K Teff ? Model effective temperature 62- 64 F3.1 [cm/s2] log(g) ? Model log surface gravity 66- 69 F4.1 [Sun] M[Fe/H] ? Model log of the Fe/H number abundance 71- 73 F3.1 km/s xi ? Microturbulence velocity 75- 79 F5.2 [Sun] [C/Fe]S ? Log of the spectral synthesis estimate of C/Fe abundance 80- 81 A2 --- u_[C/Fe]S [ :] Uncertainty flag on [C/Fe]S (2) 83- 87 F5.2 [Sun] [C/Fe]F Log of the final adopted [C/Fe] abundance
Note (2): Uncertainty flag on [C/Fe]S, defined as follows: : = uncertain; :: = highly uncertain.
Global Notes: Note (G1): Telescope(s) used in the observation, defined as follows: A = Anglo Australian 3.8m telescope; C = CTIO 4m telescope; K = KPNO 4m telescope; I = Isaac Newton 2.5m telescope; L = Las Campanas 2.5m telescope; M = McDonald Observatory 2.7m telescope; P = Palomar 5m telescope; c = CTIO 1.5m telescope; e = ESO 1.5m telescope; k = KPNO 2.1m telescope; s = SSO 2.3m telescope. Note (G2): The KP line index is a pseudo-equivalent width measure of the CaII K line (around 393nm). Note (G3): The GP line index is a fixed 15Å wide-band measure of the strength of the CH G band (around 430nm)
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 18-Jul-2006
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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