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Title: Beyond-mean-field calculations of allowed and first-forbidden β − decays of r -process waiting-point nuclei
β -decay rates of neutron-rich nuclei, in particular those located at neutron shell closures, play a central role in simulations of the heavy-element nucleosynthesis and resulting abundance distributions. We present β -decay half-lives of even-even N = 82 and N = 126 r -process waiting-point nuclei calculated in the approach based on relativistic quasiparticle random phase approximation with quasiparticle-vibration coupling. The calculations include both allowed and first-forbidden transitions. In the N = 82 chain, the quasiparticlevibration coupling has an important impact close to stability, as it increases the contribution of Gamow-Teller modes and improves the agreement with the available data. In the N = 126 chain, we find the decay to proceed dominantly via first-forbidden transitions, even when the coupling to vibrations is included.  more » « less
Award ID(s):
1654379
PAR ID:
10331514
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:
03002
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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