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Title: High‑precision measurements of half‐lives for 69Ge, 73Se, 83Sr, 85mSr, and 63Zn radionuclides relevant to the astrophysical p‑process via photoactivation at the Madison Accelerator Laboratory
The ground state half-lives of 69Ge, 73Se, 83Sr, 63Zn, and the half-life of the 1/2− isomer in 85Sr have been measured with high precision using the photoactivation technique at an unconventional bremsstrahlung facility that features a repurposed medical electron linear accelerator. The γ-ray activity was counted over about 6 half-lives with a high-purity germanium detector, enclosed into an ultra low-background lead shield. The measured half-lives are: T1/2(69Ge) = 38.82 ± 0.07 (stat) ± 0.06 (sys) h; T1/2(73Se) = 7.18 ± 0.02 (stat) ± 0.004 (sys) h; T1/2(83Sr) = 31.87 ± 1.16 (stat) ± 0.42 (sys) h; T1/2(85mSr) = 68.24 ± 0.84 (stat) ± 0.11 (sys) min; T1/2(63Zn) = 38.71 ± 0.25 (stat) ± 0.10 (sys) min. These high-precision half-life measurements will contribute to a more accurate determination of corresponding ground-state photoneutron reaction rates, which are part of a broader effort of constraining statistical nuclear models needed to calculate stellar nuclear reaction rates relevant for the astrophysical p-process nucleosynthesis.
Authors:
; ; ;
Award ID(s):
1913258
Publication Date:
NSF-PAR ID:
10251461
Journal Name:
Journal of radioanalytical and nuclear chemistry an international journal dealing with all aspects and applications of nuclear chemistry
Volume:
327
Issue:
3
Page Range or eLocation-ID:
1113 - 1120
ISSN:
1588-2780
Sponsoring Org:
National Science Foundation
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