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Title: Decay properties of 22Ne + α resonances and their impact on s-process nucleosynthesis

Journal Article · · Physics Letters B
ORCiD logo [1];  [2];  [3];  [3]; ORCiD logo [4]; ORCiD logo [4];  [3];  [3];  [4];  [4]; ORCiD logo [4]; ORCiD logo [3];  [3];  [5];  [1];  [3]; ORCiD logo [4];  [3]
  1. Texas A & M Univ., College Station, TX (United States). Cyclotron Inst.
  2. Texas A & M Univ., College Station, TX (United States). Cyclotron Inst.; Texas A & M Univ., College Station, TX (United States). Dept. of Physics and Astronomy; Texas A & M Univ., College Station, TX (United States). Nuclear Solutions Inst.
  3. Univ. of Surry, Guildford (United Kingdom). Dept. of Physics
  4. Texas A & M Univ., College Station, TX (United States). Cyclotron Inst.; Texas A & M Univ., College Station, TX (United States). Dept. of Physics and Astronomy
  5. Texas A & M Univ., College Station, TX (United States). Cyclotron Inst.; Texas A & M Univ., College Station, TX (United States). Dept. of Physics and Astronomy; Texas A & M Univ., College Station, TX (United States). Nuclear Solutions Inst
+ Show Author Affiliations

The astrophysical s-process is one of the two main processes forming elements heavier than iron. A key outstanding uncertainty surrounding s-process nucleosynthesis is the neutron flux generated by the reaction during the He-core and C-shell burning phases of massive stars. This reaction, as well as the competing reaction, is not well constrained in the important temperature regime from ~0.2–0.4 GK, owing to uncertainties in the nuclear properties of resonances lying within the Gamow window. To address these uncertainties, we have performed a new measurement of the reaction in inverse kinematics, detecting the outgoing deuterons and recoils in coincidence. We have established a new decay branching ratio of for the key MeV resonance in , which results in a new strength for this resonance of when combined with the well-established strength of this resonance. We have also determined new upper limits on the α partial widths of neutron-unbound resonances at , 11.163, 11.169, and 11.171 MeV. Monte-Carlo calculations of the stellar and rates, which incorporate these results, indicate that both rates are substantially lower than previously thought in the temperature range from ~0.2–0.4 GK.

Research Organization:
Texas A & M Univ., College Station, TX (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
NA0003841
OSTI ID:
1595170
Alternate ID(s):
OSTI ID: 1801153
Journal Information:
Physics Letters B, Vol. 802, Issue C; ISSN 0370-2693
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 14 works
Citation information provided by
Web of Science

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