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J/A+A/526/A71   C abundances in G and K nearby stars        (Da Silva+, 2011)

Homogeneous photospheric parameters and C abundances in G and K nearby stars with and without planets. Da Silva R., Milone A., Reddy B.E. <Astron. Astrophys. 526, A71 (2011)> =2011A&A...526A..71D
ADC_Keywords: Stars, nearby ; Stars, atmospheres ; Abundances ; Atomic physics Keywords: stars: fundamental parameters - stars: abundances - methods: data analysis - planetary systems Abstract: We present a determination of photospheric parameters and carbon abundances for a sample of 172 G and K dwarf, subgiant, and giant stars with and without detected planets in the solar neighbourhood. The analysis was based on high signal-to-noise ratio and high resolution spectra observed with the ELODIE spectrograph (Haute Provence Observatory, France) and for which the observational data were publicly available. We intend to contribute precise and homogeneous C abundances in studies that compare the behaviour of light elements in stars with and without planets. This will bring new arguments to the discussion of possible anomalies that have been suggested and will contribute to a better understanding of different planetary formation process. Description: The files atm_mol.dat and atm_strg.dat contain tables with atomic and molecular line parameters required by the MOOG code (Kurucz, 1995ASPC...81..CD18) to compute synthetic spectra: the rest wavelength, the line identification, the excitation potential of lower level, the oscillator strength, and the dissociation energy (only for molecular features). The line parameters of the following spectral regions are listed: from 5115 to 5170 Angstroms, containing the C2 molecular band head around 5128 and 5165; from 5360 to 5390 Angstroms, containing the Carbon atomic line at 5380.3; and the region from 5195 to 5225 Angstroms, which was also used to treat the C2 molecular band head around 5165. The opacity contributions of strong atomic lines can be distinctly considered by the MOOG code. Therefore, strong lines are listed in a separate file (atm_strg.dat). The data was taken from Kurucz (1995ASPC...81..CD18) and from the Vienna Atomic Line Database (VALD - Kupka et al. 2000BaltA...9..590K, Kupka et al. 1999A&AS..138..119K, Piskunov et al. 1995A&AS..112..525P, Ryabchikova et al. 1997BaltA...6..244R), using the "Extract Stellar" option for Teff=5777K, logg=4.44, microturbulence=1.0km/s, and a detection limit of 0.001 (which means that lines with central depths <0.1% of the continuum were rejected). In order to fit the solar spectrum, a correction factor of 0.85 was applied for C2 lines, and a correction factor of 0.5 for MgH lines. The oscillator strength values of some atomic and molecular lines were also revised when needed. The file cfe_3reg.dat contains individual Cabon abundance ratios with respect to Iron, together with their errors, computed from the three C abundance indicators studied here: the C2 molecular band head around 5128 and 5165 Angstroms, and the C atomic line at 5380.3 Angstroms. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file atm_mol.dat 43 6928 Atomic and molecular line parameters (table 2 of the paper) atm_strg.dat 34 50 Strong atomic lines (table 3 of the paper) cfe_3reg.dat 49 172 [C/Fe] abundances and errors for the three C abundance indicators: 5128, 5165, and 5380 Å (table 7 of the paper)
Byte-by-byte Description of file: atm_mol.dat
Bytes Format Units Label Explanations
2- 10 F9.4 0.1nm lambda Spectral line wavelength 13- 17 F5.1 --- Ion Atomic and molecular line identification (606 stands for C2, 112 for MgH) 20- 25 F6.3 eV chi Excitation potential 28- 36 E9.4 --- gf Oscillator strength 39- 43 F5.3 eV D0 ? Dissociation energy for molecular features
Byte-by-byte Description of file: atm_strg.dat
Bytes Format Units Label Explanations
2- 10 F9.4 0.1nm lambda Spectral line wavelength 13- 16 F4.1 --- Ion Atomic and molecular line identification 19- 23 F5.3 eV chi Excitation potential 26- 34 E9.4 --- gf Oscillator strength
Byte-by-byte Description of file: cfe_3reg.dat
Bytes Format Units Label Explanations
1- 2 A2 --- --- [HD] 4- 9 I6 --- HD HD stellar number 10 A1 --- m_HD [A] Multiplicity index on HD 13- 17 F5.2 --- CFe5128 ? Abundance ratio [C/Fe] from the 5128 region 20- 23 F4.2 --- e_CFe5128 ? Error in [C/Fe] from the 5128 region 26- 30 F5.2 --- CFe5165 ? Abundance ratio [C/Fe] from the 5165 region 33- 36 F4.2 --- e_CFe5165 ? Error in [C/Fe] from the 5165 region 39- 43 F5.2 --- CFe5380 ? Abundance ratio [C/Fe] from the 5380 line 46- 49 F4.2 --- e_CFe5380 ? Error in [C/Fe] from the 5380 line
Acknowledgements: Ronaldo Da Silva, dasilvr2(at)gmail.com
(End) Patricia Vannier [CDS] 16-Nov-2010
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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