First observation of low-energy γ-ray enhancement in the rare-earth region
Here, the γ-ray strength function and level density in the quasi-continuum of 151,153Sm have been measured using bismuth germanate shielded Ge clover detectors of the STARLiTeR system. The Compton shields allow an extraction of the γ strength down to unprecedentedly low γ energies of ≈ 500 keV. For the first time an enhanced low-energy γ-ray strength has been observed in the rare-earth region. In addition, for the first time both the upbend and the well-known scissors resonance have been observed simultaneously for the same nucleus. Hauser-Feshbach calculations show that this strength enhancement at low γ energies could have an impact of 2 3 orders of magnitude on the (n, γ) reaction rates for r-process nucleosynthesis.
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- Univ. of Notre Dame, Notre Dame, IN (United States)
- Univ. of Oslo, Oslo (Norway)
- Univ. of Richmond, Richmond, VA (United States); Univ. of Surrey, Surrey (United Kingdom)
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Univ. of Kentucky, Lexington, KY (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Texas A & M Univ., College Station, TX (United States)
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rutgers Univ., New Brunswick, NJ (United States)
- Publication Date:
- Report Number(s):
- LLNL-JRNL-704138
Journal ID: ISSN 2469-9985; KB0401022; ERKBP06
- Grant/Contract Number:
- AC52-07NA27344; AC05-00OR22725; NA0001801; FG02-05ER41379; PHY-1430152; 205528; 637686
- Type:
- Accepted Manuscript
- Journal Name:
- Physical Review C
- Additional Journal Information:
- Journal Volume: 93; Journal Issue: 3; Journal ID: ISSN 2469-9985
- Publisher:
- American Physical Society (APS)
- Research Org:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org:
- USDOE; Research Council of Norway (NFR); National Science Foundation (NSF); European Research Council (ERC)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; energy levels and level densities; photonuclear reactions; resonance reactions; 150 ≤ A ≤ 189
- OSTI Identifier:
- 1432959
- Alternate Identifier(s):
- OSTI ID: 1240452; OSTI ID: 1267050
- Free Publicly Accessible Full Text
- Accepted Manuscript (Publisher)
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Accepted Manuscript (DOE)
- Publisher's Version of Record
- https://doi.org/10.1103/PhysRevC.93.034303