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 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 2000BaltA...9..590K,
Kupka et al. 1999A&AS..138..119K 1999A&AS..138..119K, Piskunov et al. 1995A&AS..112..525P 1995A&AS..112..525P,
Ryabchikova et al. 1997BaltA...6..244R 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)
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Byte-by-byte Description of file: atm_mol.dat
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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