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J/A+A/380/578  Equiv. widths of 13 horizontal branch stars (Tautvaisiene+, 2001)

Chemical composition of red horizontal branch stars in the thick disk of the Galaxy Tautvaisiene G., Edvardsson B., Tuominen I., Ilyin I. <Astron. Astrophys. 380, 578 (2001)> =2001A&A...380..578T
ADC_Keywords: Stars, horizontal branch ; Stars, atmospheres ; Abundances Keywords: stars: abundances - stars: atmospheres - stars: horizontal-branch - Galaxy: formation Abstract: High-resolution spectra of 13 core helium-burning stars in the thick disk of the Galaxy have been obtained with the SOFIN spectrograph on the Nordic Optical Telescope to investigate abundances of up to 22 chemical elements. Abundances of carbon were studied using the C2 Swan (0, 1) band head at 5635.5Å. The wavelength interval 7980-8130Å with strong CN features was analysed in order to determine nitrogen abundances and 12C/13C isotope ratios. The oxygen abundances were determined from the [O I] line at 6300Å. Abundances in the investigated stars suggest that carbon is depleted by about 0.3dex, nitrogen is enhanced by more than 0.4dex and oxygen is unaltered. The 12C/13C ratios are lowered and lie between values 3 and 7 which is in agreement with "cool bottom processing" predictions (Boothroyd & Sackmann, 1999ApJ...510..232B). The C/N ratios in the investigated stars are lowered to values between 0.7 and 1.2 which is less than present day theoretical predictions and call for further studies of stellar mixing processes. Abundance ratios of O, Mg, Eu and other heavy chemical elements to iron in the investigated stars show a pattern characteristic of thick disk stars. The results provide evidence that the thick disk population has a distinct chemical history from the thin disk. The onset of the bulk of SN Ia is suggested to appear at [Fe/H]~-0.6dex. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file stars.dat 70 13 Star positions and magnitudes (from Simbad) table1.dat 66 204 Equivalent widths of lines
See also: J/A+A/360/499 : Equivalent widths of 9 stars of M 67 (Tautvaisiene+, 2000) Byte-by-byte Description of file: stars.dat
Bytes Format Units Label Explanations
1- 11 A11 --- Name Star name 15- 16 I2 h RAh Right ascension (J2000.0) 18- 19 I2 min RAm Right ascension (J2000.0) 21- 24 F4.1 s RAs Right ascension (J2000.0) 26 A1 --- DE- Declination sign (J2000.0) 27- 28 I2 deg DEd Declination (J2000.0) 30- 31 I2 arcmin DEm Declination (J2000.0) 33- 34 I2 arcsec DEs Declination (J2000.0) 38- 42 F5.2 mag Bmag ? B magnitude 44- 48 F5.2 mag Vmag ? V magnitude 50- 70 A21 --- SpType Spectral type
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 6 F6.2 --- Element Line identification (1) 8- 14 F7.2 0.1nm Lambda Wavelength (Angstroms) 16- 18 I3 0.1pm EW1 ?=999 Equivalent width (milliAngstrom) for the star BD +25 2436 20- 22 I3 0.1pm EW2 ?=999 Equivalent width for the star BD +25 2459 24- 26 I3 0.1pm EW3 ?=999 Equivalent width for the star BD +25 2502 28- 30 I3 0.1pm EW4 ?=999 Equivalent width for the star BD +27 2057 32- 34 I3 0.1pm EW5 ?=999 Equivalent width for the star BD +28 2079 36- 38 I3 0.1pm EW6 ?=999 Equivalent width for the star BD +29 2231 40- 42 I3 0.1pm EW7 ?=999 Equivalent width for the star BD +29 2294 44- 46 I3 0.1pm EW8 ?=999 Equivalent width for the star BD +29 2321 48- 50 I3 0.1pm EW9 ?=999 Equivalent width for the star BD +33 2280 52- 54 I3 0.1pm EW10 ?=999 Equivalent width for the star BD +34 2371 56- 58 I3 0.1pm EW11 ?=999 Equivalent width for the star BD +36 2303 60- 62 I3 0.1pm EW12 ?=999 Equivalent width for the star HD 104783 64- 66 I3 0.1pm EW13 ?=999 Equivalent width for the star HD 105944
Note (1): Chemical element and ionisation stage (e.g. 23.01 means singly ionised vanadium, or V II)
Acknowledgements: Grazina Tautvaisiene
(End) Patricia Bauer [CDS] 10-Dec-2001
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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