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Title: Exact isovector pairing in a shell-model framework: Role of proton-neutron correlations in isobaric analog states

Journal Article · · Physical Review. C
 [1]; ORCiD logo [2];  [2];  [3];  [2]
  1. Rollins College, Winter Park, FL (United States); Louisiana State Univ., Baton Rouge, LA (United States)
  2. Louisiana State Univ., Baton Rouge, LA (United States)
  3. Louisiana State Univ., Baton Rouge, LA (United States); Liaoning Normal University, Dalian (China)

Here, we utilize a nuclear shell model Hamiltonian with only two adjustable parameters to generate, for the first time, exact solutions for pairing correlations for light to medium-mass nuclei, including the challenging proton-neutron pairs, while also identifying the primary physics involved. In addition to single-particle energy and Coulomb potential terms, the shell model Hamiltonian consists of an isovector T = 1 pairing interaction and an average proton-neutron isoscalar T = 0 interaction, where the T = 0 term describes the average interaction between nonpaired protons and neutrons. This Hamiltonian is exactly solvable, where, utilizing three to seven single-particle energy levels, we reproduce experimental data for 0+ state energies for isotopes with mass A = 10 through A = 62 exceptionally well including isotopes from He to Ge. Additionally, we isolate effects due to like-particle and proton-neutron pairing, provide estimates for the total and proton-neutron pairing gaps, and reproduce N (neutron) = Z (proton) irregularity. These results provide a further understanding for the key role of proton-neutron pairing correlations in nuclei, which is especially important for waiting-point nuclei on the $$\mathcal{rp}$$ path of nucleosynthesis.

Research Organization:
Texas A & M Univ., Commerce, TX (United States)
Sponsoring Organization:
USDOE Office of Science (SC); National Science Foundation (NSF); National Natural Science Foundation of China (NSFC); State of Illinois
Grant/Contract Number:
SC0009971; 1262890; OIA-1738287; PHY-1913728; 11675071; OCI-0725070; ACI-1238993
OSTI ID:
1801969
Journal Information:
Physical Review. C, Vol. 100, Issue 6; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

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