J/A+A/434/275 Galactic thin disk [Th/Eu] abundance ratios (del Peloso+, 2005)
The age of the Galactic thin disk from Th/Eu nucleocosmochronology.
I. Determination of [Th/Eu] abundance ratios.
del Peloso E.F., da Silva L., Porto de Mello G.F.
<Astron. Astrophys. 434, 275 (2005)>
=2005A&A...434..275D 2005A&A...434..275D
ADC_Keywords: Stars, late-type ; Abundances, peculiar
Keywords: Galaxy: disk - Galaxy: evolution - stars: late-type -
stars: fundamental parameters - stars: abundances
Abstract:
The objective of this work is the determination of the age of the
Galactic disk using Th/Eu nucleocosmochronology. To achieve this
objective, it is necessary to obtain the abundances of Th and Eu
through spectral synthesis, and to perform the synthesis it is
necessary to know the atmospheric parameters and chemical
abundances of contaminating elements.
Description:
The file table6 contains all the equivalent widths of lines
used for atmospheric parameters and abundance determinations of
contaminating elements. Some lines have not been effectively used
in some stars; these have equivalent widths equal to 0.00 in the file.
All equivalent widths are presented in milli-Angstroems.
Observations with the ESO 1.52 m telescope were performed by the
authors in two runs, in March and August, 2001. All obtained FEROS
spectra have high nominal resolving power (R=48 000), signal-to-noise
ratio (S/N≥300 in the visible) and coverage (3500 to 9200Å spread
over 39 echelle orders).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 55 20 Star positions and magnitudes (from Simbad)
table6.dat 46 3360 Equivalent widths for all lines and sample stars
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Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HD]
4- 9 I6 --- HD HD number
12- 13 I2 h RAh Right ascension (J2000.0)
15- 16 I2 min RAm Right ascension (J2000.0)
18- 21 F4.1 s RAs Right ascension (J2000.0)
23 A1 --- DE- Declination sign (J2000.0)
24- 25 I2 deg DEd Declination (J2000.0)
27- 28 I2 arcmin DEm Declination (J2000.0)
30- 31 I2 arcsec DEs Declination (J2000.0)
35- 39 F5.2 mag Bmag ? B magnitude
41- 45 F5.2 mag Vmag ? V magnitude
47- 56 A10 --- SpType MK spectral type
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HD]
4- 9 I6 --- HD HD number
11- 18 F8.3 0.1nm Lambda Wavelength of line (A)
20- 22 A3 --- Element Element symbol and ionization state
24- 27 F4.2 eV EP Lower excitation potential
29- 34 F6.3 --- loggf Logarithm of oscillator strength
36- 40 F5.1 0.1pm EW0 Equivalent width of the Sun
42- 46 F5.1 0.1pm EW ?=0.00 Equivalent width of the star
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Acknowledgements: Eduardo Fernandez del Peloso, epeloso(at)on.br
(End) Patricia Vannier [CDS] 14-Jan-2005