Origin of the neutron skin thickness of {sup 208}Pb in nuclear mean-field models

Centelles, M; Roca-Maza, X; Vinas, X; Warda, M

doi:10.1103/PHYSREVC.82.054314

Title: Origin of the neutron skin thickness of {sup 208}Pb in nuclear mean-field models

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Abstract

We study whether the neutron skin thickness {Delta}r{sub np} of {sup 208}Pb originates from the bulk or from the surface of the nucleon density distributions, according to the mean-field models of nuclear structure, and find that it depends on the stiffness of the nuclear symmetry energy. The bulk contribution to {Delta}r{sub np} arises from an extended sharp radius of neutrons, whereas the surface contribution arises from different widths of the neutron and proton surfaces. Nuclear models where the symmetry energy is stiff, as typical of relativistic models, predict a bulk contribution in {Delta}r{sub np} of {sup 208}Pb about twice as large as the surface contribution. In contrast, models with a soft symmetry energy like common nonrelativistic models predict that {Delta}r{sub np} of {sup 208}Pb is divided similarly into bulk and surface parts. Indeed, if the symmetry energy is supersoft, the surface contribution becomes dominant. We note that the linear correlation of {Delta}r{sub np} of {sup 208}Pb with the density derivative of the nuclear symmetry energy arises from the bulk part of {Delta}r{sub np}. We also note that most models predict a mixed-type (between halo and skin) neutron distribution for {sup 208}Pb. Although the halo-type limit is actually found in themore »« less

Authors:

Centelles, M; Roca-Maza, X; Vinas, X ^[1]; Warda, M ^[1]

Departament d'Estructura i Constituents de la Materia and Institut de Ciencies del Cosmos, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain)

Publication Date:: Mon Nov 15 00:00:00 EST 2010

OSTI Identifier:: 21499172

Resource Type:: Journal Article

Journal Name:: Physical Review. C, Nuclear Physics

Additional Journal Information:: Journal Volume: 82; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevC.82.054314; (c) 2010 The American Physical Society; Journal ID: ISSN 0556-2813

Country of Publication:: United States

Language:: English

Subject:: 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ASYMMETRY; CORRELATIONS; DENSITY; DISTRIBUTION; ELECTRONS; FLEXIBILITY; LEAD 208; MEAN-FIELD THEORY; NEUTRONS; NUCLEAR MODELS; NUCLEAR STRUCTURE; PARITY; PROTONS; RELATIVISTIC RANGE; SCATTERING; SURFACES; SYMMETRY; THICKNESS; BARYONS; DIMENSIONS; ELEMENTARY PARTICLES; ENERGY RANGE; EVEN-EVEN NUCLEI; FERMIONS; HADRONS; HEAVY NUCLEI; ISOTOPES; LEAD ISOTOPES; LEPTONS; MATHEMATICAL MODELS; MECHANICAL PROPERTIES; NUCLEI; NUCLEONS; PARTICLE PROPERTIES; PHYSICAL PROPERTIES; STABLE ISOTOPES; TENSILE PROPERTIES

Citation Formats


                    Centelles, M, Roca-Maza, X, Vinas, X, Warda, M, and Katedra Fizyki Teoretycznej, Uniwersytet Marii Curie-Sklodowskiej, ul. Radziszewskiego 10, PL-20-031 Lublin. Origin of the neutron skin thickness of {sup 208}Pb in nuclear mean-field models.  United States: N. p., 2010. 
        Web.  doi:10.1103/PHYSREVC.82.054314.

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                    Centelles, M, Roca-Maza, X, Vinas, X, Warda, M, & Katedra Fizyki Teoretycznej, Uniwersytet Marii Curie-Sklodowskiej, ul. Radziszewskiego 10, PL-20-031 Lublin. Origin of the neutron skin thickness of {sup 208}Pb in nuclear mean-field models.  United States.  https://doi.org/10.1103/PHYSREVC.82.054314

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                    Centelles, M, Roca-Maza, X, Vinas, X, Warda, M, and Katedra Fizyki Teoretycznej, Uniwersytet Marii Curie-Sklodowskiej, ul. Radziszewskiego 10, PL-20-031 Lublin. 2010.  
        "Origin of the neutron skin thickness of {sup 208}Pb in nuclear mean-field models".  United States.  https://doi.org/10.1103/PHYSREVC.82.054314.

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@article{osti_21499172,

  title        = {Origin of the neutron skin thickness of {sup 208}Pb in nuclear mean-field models},

  author       = {Centelles, M and Roca-Maza, X and Vinas, X and Warda, M and Katedra Fizyki Teoretycznej, Uniwersytet Marii Curie-Sklodowskiej, ul. Radziszewskiego 10, PL-20-031 Lublin},

  abstractNote = {We study whether the neutron skin thickness {Delta}r{sub np} of {sup 208}Pb originates from the bulk or from the surface of the nucleon density distributions, according to the mean-field models of nuclear structure, and find that it depends on the stiffness of the nuclear symmetry energy. The bulk contribution to {Delta}r{sub np} arises from an extended sharp radius of neutrons, whereas the surface contribution arises from different widths of the neutron and proton surfaces. Nuclear models where the symmetry energy is stiff, as typical of relativistic models, predict a bulk contribution in {Delta}r{sub np} of {sup 208}Pb about twice as large as the surface contribution. In contrast, models with a soft symmetry energy like common nonrelativistic models predict that {Delta}r{sub np} of {sup 208}Pb is divided similarly into bulk and surface parts. Indeed, if the symmetry energy is supersoft, the surface contribution becomes dominant. We note that the linear correlation of {Delta}r{sub np} of {sup 208}Pb with the density derivative of the nuclear symmetry energy arises from the bulk part of {Delta}r{sub np}. We also note that most models predict a mixed-type (between halo and skin) neutron distribution for {sup 208}Pb. Although the halo-type limit is actually found in the models with a supersoft symmetry energy, the skin-type limit is not supported by any mean-field model. Finally, we compute parity-violating electron scattering in the conditions of the {sup 208}Pb parity radius experiment (PREX) and obtain a pocket formula for the parity-violating asymmetry in terms of the parameters that characterize the shape of the {sup 208}Pb nucleon densities.},

  doi          = {10.1103/PHYSREVC.82.054314},

  url          = {https://www.osti.gov/biblio/21499172},
  journal      = {Physical Review. C, Nuclear Physics},

  issn         = {0556-2813},

  number       = 5,

  volume       = 82,

  place        = {United States},

  year         = {Mon Nov 15 00:00:00 EST 2010},

  month        = {Mon Nov 15 00:00:00 EST 2010}

}

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