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J/A+A/490/769     Yields from extremely metal-poor stars   (Campbell+, 2008)

Evolution and nucleosynthesis of extremely metal poor & metal-free low- and intermediate-mass stars. I: Stellar yield tables and the CEMPs. Campbell S.W., Lattanzio J.C. <Astron. Astrophys. 490, 769 (2008)> =2008A&A...490..769C
ADC_Keywords: Models, evolutionary ; Stars, halo ; Abundances Keywords: stars: evolution - stars: interiors - Galaxy: halo - stars: AGB and post-AGB Abstract: The growing body of spectral observations of the extremely metal-poor (EMP) stars in the Galactic Halo provides constraints on theoretical studies of the chemical and stellar evolution of the early Universe. To calculate yields for EMP stars for use in chemical evolution calculations and to test whether such models can account for some of the recent abundance observations of EMP stars, in particular the highly C-rich EMP (CEMP) halo stars. We modify an existing 1D stellar structure code to include time-dependent mixing in a diffusion approximation. Using this code and a post-processing nucleosynthesis code we calculate the structural evolution and nucleosynthesis of a grid of models covering the metallicity range: -6.5≤[Fe/H]≤-3.0 (plus Z=0), and mass range: 0.85≤M≤3.0M, amounting to 20 stars in total. Description: Each of the first 5 tables contains stellar model chemical yields for 4 stars with initial masses: M=0.85, 1.0, 2.0, 3.0M at a particular metallicity. The metallicities are: Z=0 and [Fe/H]=-6.5, -5.45, -4.0, -3.0. Note that the [Fe/H]=-4.0, 3M yield is missing due to a data loss (table4.dat). We also include a table containing the remnant core masses for each star (table6.dat). The yields are given in mass fraction integrated over the lifetime of the star (see paper for details). The models were evolved from the zero age main sequence up to the end of the asymptotic giant branch (AGB) phase. Time dependent mixing was calculated using a diffusion approximation. Opacities were updated to Iglesias & Rogers (1996ApJ...464..943I) (for mid-range temperatures) and Ferguson et al. (2005ApJ...623..585F) (for low temperatures). The Reimers (1975MSRSL...8..369R) mass loss formula was used during the RGB phase and the Vassiliadis & Wood (1993ApJ...413..641V) formula during the AGB phase. No overshoot was applied. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 87 39 *Yields for Z=0.0 table2.dat 87 39 *Yields for [Fe/H]=-6.5 table3.dat 87 39 *Yields for [Fe/H]=-5.45 table4.dat 87 39 *Yields for [Fe/H]=-4.0 table5.dat 87 39 *Yields for [Fe/H]=-3.0 table6.dat 33 5 Remnant core masses for all models
Note on table1.dat, table2.dat, table3.dat, table4.dat, table5.dat: M=(0.85, 1.0, 2.0, 3.0)M
See also: VI/109 : Pop. Synth. Models at very low metallicities (Schaerer, 2003) J/A+A/285/473 : Low-mass stars (Forestini 1994) J/A+A/327/1039 : Structure and evolution of low-mass stars (Chabrier+ 1997) J/A+A/337/403 : Low-mass stars evolutionary models (Baraffe+ 1998) J/A+AS/141/371 : Low-mass stars evolutionary tracks+isochrones (Girardi+, 2000) J/ApJS/155/651 : Evolution of extremely metal-poor stars (Herwig+, 2004) J/A+A/432/861 : Yields of low and intermediate mass stars (Gavilan+, 2005) J/A+A/462/107 : Simulations of metal-poor star clusters (Fagiolini+, 2007) Byte-by-byte Description of file (# headlines): table[12345].dat
Bytes Format Units Label Explanations
1- 4 A4 --- Elem Chemical species names 7- 8 I2 --- A Nucleon number A 10- 23 E14.7 --- Init Initial abundance for this chemical species 26- 39 E14.7 --- M0.85 Yield from 0.85M_sun_ model for this species (1) 42- 55 E14.7 --- M1.00 Yield from 1.00M_sun_ model for this species (1) 58- 71 E14.7 --- M2.00 Yield from 2.00M_sun_ model for this species (1) 74- 87 E14.7 --- M3.00 ? Yield from 3.00M model for this species (1) Not calculated in table4
Note (1): In fractional mass unit.
Byte-by-byte Description of file (# headlines): table6.dat
Bytes Format Units Label Explanations
1- 5 F5.2 [Sun] [Fe/H] Metallicity (Units: [Fe/H] except for Z=0) 7- 12 F6.3 solMass Rem0.85 Remnant mass of 0.85M model at this Z 14- 19 F6.3 solMass Rem1.00 Remnant mass of 1.00M model at this Z 21- 26 F6.3 solMass Rem2.00 Remnant mass of 2.00M model at this Z 28- 33 F6.3 solMass Rem3.00 ? Remnant mass of 3.00M model at this Z
Acknowledgements: Simon Campbell, simcam(at)asiaa.sinica.edu.tw
(End) Patricia Vannier [CDS] 16-Sep-2008
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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