J/ApJ/787/10 Solar s-process contributions with GCE model (Bisterzo+, 2014)
Galactic chemical evolution and solar s-process abundances: dependence
on the 13C-pocket structure.
Bisterzo S., Travaglio C., Gallino R., Wiescher M., Kappeler F.
<Astrophys. J., 787, 10 (2014)>
=2014ApJ...787...10B 2014ApJ...787...10B (SIMBAD/NED BibCode)
ADC_Keywords: Models, evolutionary ; Sun ; Abundances ; Solar system
Keywords: stars: AGB and post-AGB - Galaxy: evolution - Sun: abundances
Abstract:
We study the s-process abundances (A≳90) at the epoch of the solar
system formation. Asymptotic giant branch yields are computed with an
updated neutron capture network and updated initial solar abundances.
We confirm our previous results obtained with a Galactic chemical
evolution (GCE) model: (1) as suggested by the s-process spread
observed in disk stars and in presolar meteoritic SiC grains, a
weighted average of s-process strengths is needed to reproduce the
solar s distribution of isotopes with A>130; and (2) an additional
contribution (of about 25%) is required in order to represent the
solar s-process abundances of isotopes from A=90 to 130. Furthermore,
we investigate the effect of different internal structures of the
13C pocket, which may affect the efficiency of the 13C(α,n)16O
reaction, the major neutron source of the s process. First, keeping
the same 13C profile adopted so far, we modify by a factor of two
the mass involved in the pocket; second, we assume a flat 13C
profile in the pocket, and we test again the effects of the variation
of the mass of the pocket. We find that GCE s predictions at the epoch
of the solar system formation marginally depend on the size and shape
of the 13C pocket once a different weighted range of 13C-pocket
strengths is assumed. We obtain that, independently of the internal
structure of the 13C pocket, the missing solar system s-process
contribution in the range from A=90 to 130 remains essentially the same.
Description:
The general structure of the GCE model adopted in this work is the
same described by Travaglio et al. (2004ApJ...601..864T 2004ApJ...601..864T). The GCE
model follows the composition of stars, stellar remnants, interstellar
matter (atomic and molecular gas), and their mutual interaction, in
the three main zones of the Galaxy, halo, thick disk, and thin disk.
We concentrate on the chemical evolution inside the solar annulus,
located 8.5 kpc from the Galactic center. The thin disk is divided
into independent concentric annuli, and we neglect any dependence on
Galactocentric radius.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 76 207 Solar s-process contributions for isotopes from
Kr to Bi obtained with GCE model
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See also:
J/MNRAS/418/284 : s-process in low-metallicity stars. II. (Bisterzo+, 2011)
J/A+A/586/A49 : r- and s- process elements in Milky Way disk
(Battistini+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Isotope Isotope identifier
9 A1 --- f_Isotope [bc] Flag on Isotope (1)
11- 15 F5.1 % Main-s Bisterzo et al. (2011, J/MNRAS/418/284)
main-s contribution (2)
17 A1 --- f_Main-s [cd] Flag on Main-s (3)
19- 22 F4.1 % e_Main-s ? Uncertainty in Main-s (4)
24- 29 F6.2 % T04-LMS Travaglio et al. (2004ApJ...601..864T 2004ApJ...601..864T) LMS
Solar s-process distribution
31 A1 --- f_T04-LMS [d] Flag on T04-LMS (3)
33- 37 F5.2 % T04-IMS Travaglio et al. (2004ApJ...601..864T 2004ApJ...601..864T) IMS
Solar s-process distribution
39- 43 F5.1 % T04+ Travaglio et al. (2004ApJ...601..864T 2004ApJ...601..864T) LMS+IMS
Solar s-process distribution
45- 46 A2 --- f_T04+ [cd ] Flag on T04+ (3)
47- 49 F3.1 % e_T04+ ? Uncertainty in T04+ (4)
51- 55 F5.2 % TW-LMS This work LMS Solar s-process distribution
57 A1 --- f_TW-LMS [cd] Flag on LMS (3)
59- 62 F4.2 % TW-IMS This work IMS Solar s-process distribution
64- 69 F6.2 % TW+ This work LMS+IMS Solar s-process distribution
71 A1 --- f_TW+ [d] Flag on TW+ (3)
73- 76 F4.1 % e_TW+ ? Uncertainty in TW+ (4)
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Note (1): Flag as follows:
b = Note that massive stars may produce a consistent amount of Kr-Rb-Sr-Y-Zr,
and in minor quantity up to Te-Xe (Pignatari et al. 2010ApJ...710.1557P 2010ApJ...710.1557P;
2013ApJ...762...31P 2013ApJ...762...31P).
c = An isotope that receives an additional contribution from p-process
(Travaglio et al. 2011ApJ...739...93T 2011ApJ...739...93T).
Note (2): The main-s component, which is reproduced as an average between AGB
models of M=1.5 and 3 M☉ and half solar metallicity, as in
Arlandini et al. (1999ApJ...525..886A 1999ApJ...525..886A), is also listed for comparison.
Note (3): Flag as follows:
c = Overabundance with respect to solar (in percentage).
d = Percentages include the s-contribution (≤1%) by r-only isotopes not
included in this table (124Sn, 130Te, 136Xe, 150Nd).
Note (4): Uncertainties refer to solar abundances by Anders & Grevesse
(1989GeCoA..53..197A 1989GeCoA..53..197A; T04+) and Lodders et al. (2009, LanB, 4, 44;
Main-s and TW+).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 03-Aug-2017