Fission Fragment Intrinsic Spins and Their Correlations

Journal Article · Wed Apr 07 00:00:00 EDT 2021 · Physical Review Letters

DOI:https://doi.org/10.1103/physrevlett.126.142502· OSTI ID:1774896

Bulgac, Aurel ^[1]; Abdurrahman, Ibrahim ^[2]; Jin, Shi ^[2]; Godbey, Kyle ^[3]; Schunck, Nicolas ^[4]; Stetcu, Ionel ^[5]

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1. Univ. of Washington, Seattle, WA (United States); University of Washington
2. Univ. of Washington, Seattle, WA (United States)
3. Texas A & M Univ., College Station, TX (United States)
4. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
5. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

The intrinsic spins and their correlations are the least understood characteristics of fission fragments from both theoretical and experimental points of view. In many nuclear reactions, the emerging fragments are typically excited and acquire an intrinsic excitation energy and an intrinsic spin depending on the type of the reactions and interaction mechanism. Both the intrinsic excitation energies and the fragments’ intrinsic spins and parities are controlled by the interaction mechanism and conservations laws, which lead to their correlations and determines the character of their deexcitation mechanism. We outline here a framework for the theoretical extraction of the intrinsic spin distributions of the fragments and their correlations within the fully microscopic real-time density-functional theory formalism and illustrate it on the example of induced fission of ²³⁶U and ²⁴⁰Pu, using two nuclear energy density functionals. Here, these fission fragment intrinsic spin distributions display new qualitative features previously not discussed in literature. Within this fully microscopic framework, we extract for the first time the intrinsic spin distributions of fission fragments of ²³⁶U and ²⁴⁰Pu as well as the correlations of their intrinsic spins, which have been debated in literature for more than six decades with no definite conclusions so far.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Univ. of Washington, Seattle, WA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR); USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: 89233218CNA000001; AC52-07NA27344; FG02-97ER41014; NA0003841
• OSTI ID: 1774896
• Alternate ID(s): OSTI ID: 1804287; OSTI ID: 1804367
• Report Number(s): LA-UR--20-30404; LLNL-JRNL--819588
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 14 Vol. 126; ISSN 0031-9007
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
fission
microscopic real-time density-functional theory formalism
nuclear density functional theory
nuclear reactions
nuclear spin & parity
nuclear structure & decays