J/A+A/592/A111 Evolution of long-lived globular cluster stars (Chantereau+ 2016)
Evolution of long-lived globular cluster stars.
III. Effect of the initial helium spread on the position of stars in a synthetic
Hertzsprung-Russel diagram.
Chantereau W., Charbonnel C., Meynet G.
<Astron. Astrophys. 592, A111 (2016)>
=2016A&A...592A.111C 2016A&A...592A.111C (SIMBAD/NED BibCode)
ADC_Keywords: Models ; Clusters, globular
Keywords: stars: abundances - stars: evolution - stars: low-mass -
globular clusters: general - stars: chemically peculiar
Abstract:
Globular clusters host multiple populations of long-lived low-mass
stars whose origin remains an open question. Several scenarios have
been proposed to explain the associated photometric and spectroscopic
peculiarities. They differ, for instance, in the maximum helium
enrichment they predict for stars of the second population, which
these stars can inherit at birth as the result of the internal
pollution of the cluster by different types of stars of the first
population.
We present the distribution of helium-rich stars in present-day
globular clusters as it is expected in the original framework of the
fast-rotating massive stars scenario (FRMS) as first-population
polluters. We focus on NGC 6752.
We completed a grid of 330 stellar evolution models for globular
cluster low-mass stars computed with different initial chemical
compositions corresponding to the predictions of the original FRMS
scenario for [Fe/H]=-1.75. Starting from the initial helium-sodium
relation that allows reproducing the currently observed distribution
of sodium in NGC 6752, we deduce the helium distribution expected in
that cluster at ages equal to 9 and 13Gyr. We distinguish the stars
that are moderately enriched in helium from those that are very
helium-rich (initial helium mass fraction below and above 0.4,
respectively), and compare the predictions of the FRMS framework with
other scenarios for globular cluster enrichment.
Description:
We present a grid of 224 stellar evolution models for low-mass stars
with initial masses between 0.3 and 1.0M☉ and initial helium
mass fraction between 0.248 and 0.8 computed for [Fe/H]=-1.75 with the
stellar evolution code STAREVOL.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 18 15 List of files
models/* . 15 Individual files
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 4 F4.2 Msun Mini Initial mass of the model
7- 18 A12 --- FileName Name of the file in subdirectory models (1)
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Note (1): In each files, there are 22 models with different initial helium from
0.248 (in mass fraction) to 0.8 -> [0.248,0.26,0.27,0.3,0.33,0.37,0.4,0.425,
0.45,0.475,0.5,0.525,0.55,0.575,0.6,0.625,0.65,0.675,0.7,0.73,0.77,0.8]
Before each set of data, there is a header displaying the number of lines for
each model (up to 500), the initial mass and the initial helium mass fraction
(e.g. 500 0.80 0.248)
The number of the line represents the following points (if possible):
Number 101 -> Zero age main sequence
Number 211 -> Turn-off
Number 271 -> Base of the RGB
Number 291 -> RGB tip
Number 451 -> Base of the AGB
Number 500 -> Maximum of luminosity of the AGB
Content of the files:
Byte-by-byte Description of file: models/*.dat
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Bytes Format Units Label Explanations
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1- 24 E24.19 --- Model Model number
26- 49 E24.19 K Tmax Maximum temperature
51- 74 E24.19 Msun Mass Mass coordinate of Tmax
76- 99 E24.19 K Teff Effective temperature
101- 124 E24.19 Lsun L Surface luminosity
126- 149 E24.19 Rsun Reff Photospheric radius
151- 174 E24.19 g/cm3 rhoeff Photospheric density
176- 199 E24.19 g/cm3 rhomax Density at the location of Tmax
201- 224 E24.19 Msun M Stellar mass
226- 249 E24.19 Msun/yr DM/dt Mass-loss rate
251- 274 E24.19 yt t Age
276- 299 E24.19 [cm/s2] log(geff) Photospheric gravity
301- 324 E24.19 K Tc Central temperature
326- 349 E24.19 --- Pc Central pressure
351- 374 E24.19 Msun Menv Mass at the base of the convective envelope
376- 399 E24.19 Msun Mcode Mass of the core
401- 424 E24.19 --- H1 H1 surface abundance
426- 449 E24.19 --- H2 H2 surface abundance
451- 474 E24.19 --- He3 He3 surface abundance
476- 499 E24.19 --- He4 He4 surface abundance
501- 524 E24.19 --- Li6 Li6 surface abundance
526- 549 E24.19 --- Li7 Li7 surface abundance
551- 574 E24.19 --- Be7 Be7 surface abundance
576- 599 E24.19 --- Be9 Be9 surface abundance
601- 624 E24.19 --- B10 B10 surface abundance
626- 649 E24.19 --- B11 B11 surface abundance
651- 674 E24.19 --- C12 C12 surface abundance
676- 699 E24.19 --- C13 C13 surface abundance
701- 724 E24.19 --- C14 C14 surface abundance
726- 749 E24.19 --- N14 N14 surface abundance
751- 774 E24.19 --- N15 N15 surface abundance
776- 799 E24.19 --- O16 O16 surface abundance
801- 824 E24.19 --- O17 O17 surface abundance
826- 849 E24.19 --- O18 O18 surface abundance
851- 874 E24.19 --- F19 F19 surface abundance
876- 899 E24.19 --- Ne20 Ne20 surface abundance
901- 924 E24.19 --- Ne21 Ne21 surface abundance
926- 949 E24.19 --- Ne22 Ne22 surface abundance
951- 974 E24.19 --- Na23 Na23 surface abundance
976- 999 E24.19 --- Mg24 Mg24 surface abundance
1001-1024 E24.19 --- Mg25 Mg25 surface abundance
1026-1049 E24.19 --- Mg26 Mg26 surface abundance
1051-1074 E24.19 --- Al26m Al26m surface abundance
1076-1099 E24.19 --- Al26g Al26g surface abundance
1101-1124 E24.19 --- Al27 Al27 surface abundance
1126-1149 E24.19 --- Si28 Si28 surface abundance
1151-1174 E24.19 --- H1c H1 central abundance
1176-1199 E24.19 --- He3c He3 central abundance
1201-1224 E24.19 --- He4c He4 central abundance
1226-1249 E24.19 --- C12c C12 central abundance
1251-1274 E24.19 --- C13c C13 central abundance
1276-1299 E24.19 --- C14c C14 central abundance
1301-1324 E24.19 --- N14c N14 central abundance
1326-1349 E24.19 --- O16c O16 central abundance
1351-1374 E24.19 --- O17c O17 central abundance
1376-1399 E24.19 --- O18c O18 central abundance
1401-1424 E24.19 --- F19c F19 central abundance
1426-1449 E24.19 --- Ne20c Ne20 central abundance
1451-1474 E24.19 --- Ne21c Ne21 central abundance
1476-1499 E24.19 --- Ne22c Ne22 central abundance
1501-1524 E24.19 --- Na23c Na23 central abundance
1526-1549 E24.19 --- Mg24c Mg24 central abundance
1551-1574 E24.19 --- Mg25c Mg25 central abundance
1576-1599 E24.19 --- Mg26c Mg26 central abundance
1601-1624 E24.19 --- Al26mc Al26m central abundance
1626-1649 E24.19 --- Al26gc Al26g central abundance
1651-1674 E24.19 --- Al27c Al27 central abundance
1676-1699 E24.19 --- Si28c Si28 central abundance
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History:
Copied at http://obswww.unige.ch/Recherche/evol/starevol/Globular.php
References:
Chantereau et al., Paper I 2015A&A...578A.117C 2015A&A...578A.117C
Charbonnel & Chantereau, Paper II 2016A&A...586A..21C 2016A&A...586A..21C
(End) Patricia Vannier [CDS] 04-Aug-2016