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Title: r-Process Contributions to Low-Metallicity Stars
Various nucleosynthesis studies have pointed out that the rapid neutron capture r-process elements in very metal-poor (VMP) halo stars might have different origins. It has been known that an r-process can either be obtained in neutron-rich low Ye conditions or in high entropy environments [see e.g. 1–5], an overview over many investigations has appeared recently [6]. In the present article we analyze with statistical methods the observational abundance patterns from trans-Fe elements up to the actinides and come to the conclusion that four to five categories of astrophysical events must have contributed. These include the ejection of Fe and trans-Fe elements Sr, Y, Zr (continuing possibly beyond to slightly higher mass numbers) in category 0 events (hereafter "C0"), Fe and weak r-process contributions (including Eu in moderate to slightly larger but varying amounts) in CI and CII events, strong r-process abundance patterns with no or negligible (in comparison to solar) Fe production in CIIIa and CIIIb events, where category CIIIb shows a tendency for an actinide boost behavior. When comparing these categories with presently existing nucleosynthesis predictions, we suggest to identify them (despite remaining uncertainties) with regular core-collapse supernovae, quark deconfinement supernovae, magneto-rotational supernovae, neutron star mergers, and outflows from black hole accretion tori.  more » « less
Award ID(s):
1927130
NSF-PAR ID:
10358444
Author(s) / Creator(s):
; ; ;
Editor(s):
Liu, W.; Wang, Y.; Guo, B.; Tang, X.; Zeng, S.
Date Published:
Journal Name:
EPJ Web of Conferences
Volume:
260
ISSN:
2100-014X
Page Range / eLocation ID:
09002
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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