Proton-neutron pairing and alpha-type condensation in nuclei

Sandulescu, N.; Negrea, D.; Gambacurta, D.

doi:10.1063/1.4932274

Title: Proton-neutron pairing and alpha-type condensation in nuclei

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Abstract

We summarize a recent work (N. Sandulescu et al, arXiv:1507.04144) on isoscalar and isovector proton-neutron pairing treated in a formalism which conserves exactly the particle number and the isospin. The formalism is designed for self-conjugate (N=Z) systems of nucleons moving in an axially deformed mean field and interacting through the most general isovector and isoscalar pairing interactions. The ground state of these systems is described by a superposition of two types of condensates, i.e., condensates of isovector quartets, built by two isovector pairs coupled to the total isospin T=0, and condensates of isoscalar proton-neutron pairs. The comparison with the exact solutions of realistic isovector-isoscalar pairing Hamiltonians shows that this formalism is able to describe accurately the pairing correlations energies. It is also shown that, contrary to the majority of HFB calculations, in the present formalism the isovector and isoscalar pairing correlations coexist together for any pairing interactions.

Authors:

Sandulescu, N.; Negrea, D. ^[1]; Gambacurta, D. ^[2]

National Institute of Physics and Nuclear Engineering, P.O. Box MG-6, 76900 Bucharest-Magurele (Romania)
Istituto Nazionale di Fisica Nucleare - Sezione di Catania Via S. Sofia 64, I-95123 Catania (Italy)

Publication Date:: Thu Oct 15 00:00:00 EDT 2015

OSTI Identifier:: 22492471

Resource Type:: Journal Article

Journal Name:: AIP Conference Proceedings

Additional Journal Information:: Journal Volume: 1681; Journal Issue: 1; Conference: Nuclear Structure and Dynamics '15: 3. international nuclear physics conference on nuclear structure and dynamics, Portoroz (Slovenia), 14-19 Jun 2015; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0094-243X

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; COMPARATIVE EVALUATIONS; CONDENSATES; ELECTRON CORRELATION; EXACT SOLUTIONS; GROUND STATES; HAMILTONIANS; ISOSPIN; ISOVECTORS; MEAN-FIELD THEORY; NEUTRONS; NUCLEI; PAIRING INTERACTIONS; PROTONS

Citation Formats


                    Sandulescu, N., Negrea, D., and Gambacurta, D. Proton-neutron pairing and alpha-type condensation in nuclei.  United States: N. p., 2015. 
        Web.  doi:10.1063/1.4932274.

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                    Sandulescu, N., Negrea, D., & Gambacurta, D. Proton-neutron pairing and alpha-type condensation in nuclei.  United States.  https://doi.org/10.1063/1.4932274

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                    Sandulescu, N., Negrea, D., and Gambacurta, D. 2015.  
        "Proton-neutron pairing and alpha-type condensation in nuclei".  United States.  https://doi.org/10.1063/1.4932274.

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@article{osti_22492471,

  title        = {Proton-neutron pairing and alpha-type condensation in nuclei},

  author       = {Sandulescu, N. and Negrea, D. and Gambacurta, D.},

  abstractNote = {We summarize a recent work (N. Sandulescu et al, arXiv:1507.04144) on isoscalar and isovector proton-neutron pairing treated in a formalism which conserves exactly the particle number and the isospin. The formalism is designed for self-conjugate (N=Z) systems of nucleons moving in an axially deformed mean field and interacting through the most general isovector and isoscalar pairing interactions. The ground state of these systems is described by a superposition of two types of condensates, i.e., condensates of isovector quartets, built by two isovector pairs coupled to the total isospin T=0, and condensates of isoscalar proton-neutron pairs. The comparison with the exact solutions of realistic isovector-isoscalar pairing Hamiltonians shows that this formalism is able to describe accurately the pairing correlations energies. It is also shown that, contrary to the majority of HFB calculations, in the present formalism the isovector and isoscalar pairing correlations coexist together for any pairing interactions.},

  doi          = {10.1063/1.4932274},

  url          = {https://www.osti.gov/biblio/22492471},
  journal      = {AIP Conference Proceedings},

  issn         = {0094-243X},

  number       = 1,

  volume       = 1681,

  place        = {United States},

  year         = {Thu Oct 15 00:00:00 EDT 2015},

  month        = {Thu Oct 15 00:00:00 EDT 2015}

}

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