J/A+A/496/223 PMS tracks at low Z for 0.1≤M≤1.5 (Di Criscienzo+, 2009)
Updated pre-main sequence tracks at low metallicities for 0.1≤M/M☉≤1.5.
Di Criscienzo M., Ventura P., D'antona F.
<Astron. Astrophys., 496, 223-227 (2009)>
=2009A&A...496..223D 2009A&A...496..223D
ADC_Keywords: Stars, pre-main sequence ; Models, evolutionary
Keywords: stars: evolution - stars: pre-main sequence
Abstract:
While MLT-alpha2D models are not available for lower metallicities,
we extend to lower Z the NEMO-FST models, under the hypothesis that in
such a way we are simulating the results of MLT-alpha2D models also
at smaller Z.
We use standard stellar computation techniques in which the
atmospheric boundary conditions are derived making use of model
atmosphere grids. This allows us to take into account the non greyness
of the atmosphere, but adds a new parameter to the stellar structure
uncertainty, namely the efficiency of convection in the atmospheric
structure, if convection is computed in the atmospheric grid by a
model different to the model adopted for the interior integration.
Description:
We present pre-main-sequence (PMS) models for low mass stars from
0.1 to 1.5M_☉ for metallicities [Fe/H]=-0.5, -1.0 and -2.0.
The calculations include the most recent interior physics and the
latest generation of non-grey atmosphere models. At fixed luminosity
more metal poor isochrones are hotter than solar ones by
ΔlogTeff/ΔlogZ∼0.03-0.05 in the range in Z from 0.02
to 0.0002 and for ages from 105 to 107yr.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tracks.dat 51 3775 Evolutionary tracks
iso.dat 34 108 Isochrones
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See also:
VI/109 : Population Synthesis Models at very low Z (Schaerer, 2003)
VI/113 : Evolutionary models of Population II stars (Cariulo+, 2004)
J/A+A/361/1023 : Evolution models for α-enhanced stars (Salasnich+ 2000)
J/A+AS/141/371 : Low-mass stars evolutionary tracks+isochrones (Girardi+, 2000)
J/A+A/484/815 : Scaled solar tracks and isochrones (Bertelli+, 2008)
J/A+A/494/209 : Pre-main sequence evolutionary tracks (Landin+, 2009)
Byte-by-byte Description of file: tracks.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Code [AH97 NEMO] Code used (1)
6- 11 F6.4 --- Z Initial metallicity (0.0002, 0.002 or 0.006)
13- 16 F4.2 solMass Mass Initial mass (from 0.1 to 1.5)
19- 27 F9.6 [yr] log(Age) Stellar age
31- 39 F9.6 [solLum] logL Luminosity
44- 51 F8.6 [K] log(Teff) Effective temperature
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Note (1): Codes as follows:
AH97 = MLT (Mixing Length Theory) non grey models based on the atmosphere
structure by Allard & Hauschildt (1997, The NEXTGEN model grids,
http://hobbes.hs.uni-hamburg.de/yeti/mdwarfs.html); used for
low very low masses
NEMO = FST (with CGM convection) non grey models based on ATLAS-9
grid by Heiter et al. (2002A&A...392..619H 2002A&A...392..619H)
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Byte-by-byte Description of file: iso.dat
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Bytes Format Units Label Explanations
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1- 6 F6.4 --- Z Isochone metallicity (0.0002, 0.002 or 0.006)
8- 11 E4.1 yr Age Isochone age (1e+5, 1e+6 or 1e+7)
15- 18 F4.2 solMass Mass Mass (from 0.1 to 1.5)
22- 26 F5.3 [K] log(Teff) Effective temperature
29- 34 F6.3 [solLum] logL Luminosity
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History:
Copied at http://www.mporzio.astro.it/~tsa/
(End) Patricia Vannier [CDS] 18-May-2009