Neutron-capture elements in dwarf galaxies
نویسندگان
چکیده
منابع مشابه
Neutron-capture Elements in the Metal-poor Globular Cluster M15
We report on observations of six giants in the globular cluster M15 (NGC 7078) using the Subaru Telescope to measure neutron-capture elemental abundances. Our abundance analyses based on high-quality blue spectra confirm the star-to-star scatter in the abundances of heavy neutron-capture elements (e.g., Eu), and no significant s-process contribution to them, as was found in previous studies. We...
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We present results from an ongoing survey of the infrared emission lines [Kr III] 2.199 and [Se IV] 2.287 μm in Galactic planetary nebulae (PNe). Krypton and selenium may be produced by slow neutron-capture nucleosynthesis (the “s-process”) during the asymptotic giant branch (AGB) phase of PN progenitor stars, and brought to the surface by convective dredge-up before PN ejection. We detect emis...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2019
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201936125