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The Rise of the s-Process in the Galaxy

Simmerer, Jennifer LU ; Sneden, Christopher; Cowan, John; Collier, Jason; Woolf, Vincent and Lawler, James (2004) In The Astrophysical Journal 617(2). p.1091-1114
Abstract
From newly obtained high-resolution, high signal-to-noise ratio spectra the abundances of the elements La and Eu have been determined over the stellar metallicity range -3<[Fe/H]<+0.3 in 159 giant and dwarf stars. Lanthanum is predominantly made by the s-process in the solar system, while Eu owes most of its solar system abundance to the r-process. The changing ratio of these elements in stars over a wide metallicity range traces the changing contributions of these two processes to the Galactic abundance mix. Large s-process abundances can be the result of mass transfer from very evolved stars, so to identify these cases we also report carbon abundances in our metal-poor stars. Results indicate that the s-process may be active as... (More)
From newly obtained high-resolution, high signal-to-noise ratio spectra the abundances of the elements La and Eu have been determined over the stellar metallicity range -3<[Fe/H]<+0.3 in 159 giant and dwarf stars. Lanthanum is predominantly made by the s-process in the solar system, while Eu owes most of its solar system abundance to the r-process. The changing ratio of these elements in stars over a wide metallicity range traces the changing contributions of these two processes to the Galactic abundance mix. Large s-process abundances can be the result of mass transfer from very evolved stars, so to identify these cases we also report carbon abundances in our metal-poor stars. Results indicate that the s-process may be active as early as [Fe/H]=-2.6, although we also find that some stars as metal-rich as [Fe/H]=-1 show no strong indication of s-process enrichment. There is a significant spread in the level of s-process enrichment even at solar metallicity. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
The Astrophysical Journal
volume
617
issue
2
pages
1091 - 1114
publisher
University of Chicago Press
external identifiers
  • Scopus:13944273470
language
English
LU publication?
no
id
3033da09-88ca-48c9-9c82-557e43e24a63 (old id 964926)
date added to LUP
2008-01-29 11:13:47
date last changed
2016-10-13 04:58:16
@misc{3033da09-88ca-48c9-9c82-557e43e24a63,
  abstract     = {From newly obtained high-resolution, high signal-to-noise ratio spectra the abundances of the elements La and Eu have been determined over the stellar metallicity range -3&lt;[Fe/H]&lt;+0.3 in 159 giant and dwarf stars. Lanthanum is predominantly made by the s-process in the solar system, while Eu owes most of its solar system abundance to the r-process. The changing ratio of these elements in stars over a wide metallicity range traces the changing contributions of these two processes to the Galactic abundance mix. Large s-process abundances can be the result of mass transfer from very evolved stars, so to identify these cases we also report carbon abundances in our metal-poor stars. Results indicate that the s-process may be active as early as [Fe/H]=-2.6, although we also find that some stars as metal-rich as [Fe/H]=-1 show no strong indication of s-process enrichment. There is a significant spread in the level of s-process enrichment even at solar metallicity.},
  author       = {Simmerer, Jennifer and Sneden, Christopher and Cowan, John and Collier, Jason and Woolf, Vincent and Lawler, James},
  language     = {eng},
  number       = {2},
  pages        = {1091--1114},
  publisher    = {ARRAY(0x9578f60)},
  series       = {The Astrophysical Journal},
  title        = {The Rise of the s-Process in the Galaxy},
  volume       = {617},
  year         = {2004},
}