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Title: The Influence of β-decay Rates on r-process Observables
Abstract

The rapid neutron capture process (r-process) is one of the main mechanisms whereby elements heavier than iron are synthesized, and is entirely responsible for the natural production of the actinides. Kilonova emissions are modeled as being largely powered by the radioactive decay of species synthesized via ther-process. Given that ther-process occurs far from nuclear stability, unmeasured beta-decay rates play an essential role in setting the timescale for ther-process. In an effort to better understand the sensitivity of kilonova modeling to different theoretical global beta-decay descriptions, we incorporate these into nucleosynthesis calculations. We compare the results of these calculations and highlight differences in kilonova nuclear energy generation and light-curve predictions, as well as final abundances and their implications for nuclear cosmochronometry. We investigate scenarios where differences in beta-decay rates are responsible for increased nuclear heating on timescales of days that propagates into a significantly increased average bolometric luminosity between 1 and 10 days post-merger. We identify key nuclei, both measured and unmeasured, whose decay rates directly impact nuclear heating generation on timescales responsible for light-curve evolution. We also find that uncertainties in beta-decay rates significantly impact age estimates from cosmochronometry.

 
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Award ID(s):
2020275
NSF-PAR ID:
10398185
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
944
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 144
Size(s):
["Article No. 144"]
Sponsoring Org:
National Science Foundation
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