Neutron Capture Elements in s-Process-Rich, Very Metal-Poor Stars
نویسندگان
چکیده
National Astronomical Observatory, Mitaka, Tokyo, 181-8588 Japan; email: [email protected], [email protected], [email protected], [email protected] Department of Physics and Astronomy, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK; email: [email protected] Research School of Astronomy and Astrophysics, The Australian National University, Private Bag, Weston Creek Post Office, Canberra, ACT 2611, Australia; email: [email protected] Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-1116, USA; email:
منابع مشابه
Neutron-capture elements in the s- and r-process-rich stars: Constraints on neutron-capture nucleosynthesis processes
The chemical abundances of the very metal-poor double-enhanced stars are excellent information for setting new constraints on models of neutron-capture processes at low metallicity. These stars are known as s+r stars, since they show enhancements of both s-process and r-process elements. The observed abundance ratios for the double-enhanced stars can be explained by those of stars that were pol...
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متن کاملDetection of Lead in the Carbon-rich, Very Metal-poor Star LP 625-44: A Strong Constraint on s-Process Nucleosynthesis at Low Metallicity.
We report the detection of the Pb i lambda4057.8 line in the very metal-poor (&sqbl0;Fe&solm0;H&sqbr0;=-2.7), carbon-rich star, LP 625-44. We determine the abundance of Pb (&sqbl0;Pb&solm0;Fe&sqbr0;=2.65) and 15 other neutron-capture elements. The abundance pattern between Ba and Pb agrees well with a scaled solar system s-process component, while the lighter elements (Sr-Zr) are less abundant ...
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