Elemental Abundances in M31: Iron and Alpha Element Abundances in M31’s Outer Halo
نویسندگان
چکیده
منابع مشابه
Sulphur and iron abundances in halo stars
From equivalent widths of the S i lines at 8694 Å, Israelian & Rebolo (2001) and Takada-Hidai et al. (2002) have derived a surprisingly high sulphur-to-iron ratio ([S/Fe] ≃ 0.5 to 0.7) in six halo stars with [Fe/H] ≃ −2.0 suggesting perhaps that hypernovae made a significant contribution to the formation of elements in the early Galaxy. To investigate this problem we have used high-resolution s...
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Abundance comparisons of neutron-capture elements – those formed in slow (sprocess) and rapid (r-process) neutron-capture nucleosynthesis – are providing important new information about the nature of the earliest Galactic nucleosynthesis and the first stellar generations (see recent reviews by Truran et al. 2002, Sneden & Cowan 2003 and Cowan & Thielemann 2004). Most previous studies have been ...
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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 2020
ISSN: 1538-3881
DOI: 10.3847/1538-3881/ab9602