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Title: Giant neutron halos in the non-relativistic mean field approach

Abstract

Giant neutron halos in medium-heavy nuclei are studied in the framework of the Hartree-Fock-Bogoliubov (HFB) approach with Skyrme interactions. The appearance of such structures depends sensitively on the effective interaction adopted. This is illustrated by comparing the predictions of SLy4 and SkI4 in the Ca and Zr isotopic chains. The latter force predicts a neutron halo in the Zr chain with A>122 due to the weakly bound orbitals 3p1/2 and 3p3/2. It is found that the energies of states near the separation threshold depend sensitively on effective mass values. The structure of the halo is analyzed in terms of the occupation probabilities of these orbitals and their partial contributions to the neutron density. The antihalo effect is also discussed in the case of {sup 124}Zr by comparing the occupation probabilities and wave functions of the Hartree-Fock neutron single-particle states near the Fermi energy with the corresponding HFB quasiparticle states.

Authors:
 [1];  [2];  [2];  [1];  [3];  [4];  [5];  [1]
  1. Institut de Physique Nucleaire, 15 rue Georges Clemenceau, F-91406 Orsay Cedex (France)
  2. (Italy)
  3. (Japan)
  4. Service de Physique Nucleaire, CEA-DAM Ile-de-France, BP 12, F-91680 Bruyeres-le-Cha circumflex tel (France)
  5. (Romania)
Publication Date:
OSTI Identifier:
20864205
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 74; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevC.74.064317; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; CALCIUM ISOTOPES; EFFECTIVE MASS; HARTREE-FOCK METHOD; HARTREE-FOCK-BOGOLYUBOV THEORY; HEAVY NUCLEI; INTERMEDIATE MASS NUCLEI; MEAN-FIELD THEORY; NEUTRON DENSITY; NEUTRONS; NUCLEAR HALOS; PROBABILITY; RELATIVISTIC RANGE; SINGLE-PARTICLE MODEL; SKYRME POTENTIAL; WAVE FUNCTIONS; ZIRCONIUM ISOTOPES

Citation Formats

Grasso, M., Dipartimento di Fisica e Astronomia, Via Santa Sofia 64, I-95123 Catania, INFN, Sezione di Catania, Via Santa Sofia 64, I-95123 Catania, Yoshida, S., Science Research Center, Hosei University, 2-17-1 Fujimi, Chiyoda, Tokyo 102-8160, Sandulescu, N., Institute for Physics and Nuclear Engineering, P.O. Box MG-6, RO-76900 Bucharest, and Van Giai, N.. Giant neutron halos in the non-relativistic mean field approach. United States: N. p., 2006. Web. doi:10.1103/PHYSREVC.74.064317.
Grasso, M., Dipartimento di Fisica e Astronomia, Via Santa Sofia 64, I-95123 Catania, INFN, Sezione di Catania, Via Santa Sofia 64, I-95123 Catania, Yoshida, S., Science Research Center, Hosei University, 2-17-1 Fujimi, Chiyoda, Tokyo 102-8160, Sandulescu, N., Institute for Physics and Nuclear Engineering, P.O. Box MG-6, RO-76900 Bucharest, & Van Giai, N.. Giant neutron halos in the non-relativistic mean field approach. United States. doi:10.1103/PHYSREVC.74.064317.
Grasso, M., Dipartimento di Fisica e Astronomia, Via Santa Sofia 64, I-95123 Catania, INFN, Sezione di Catania, Via Santa Sofia 64, I-95123 Catania, Yoshida, S., Science Research Center, Hosei University, 2-17-1 Fujimi, Chiyoda, Tokyo 102-8160, Sandulescu, N., Institute for Physics and Nuclear Engineering, P.O. Box MG-6, RO-76900 Bucharest, and Van Giai, N.. Fri . "Giant neutron halos in the non-relativistic mean field approach". United States. doi:10.1103/PHYSREVC.74.064317.
@article{osti_20864205,
title = {Giant neutron halos in the non-relativistic mean field approach},
author = {Grasso, M. and Dipartimento di Fisica e Astronomia, Via Santa Sofia 64, I-95123 Catania and INFN, Sezione di Catania, Via Santa Sofia 64, I-95123 Catania and Yoshida, S. and Science Research Center, Hosei University, 2-17-1 Fujimi, Chiyoda, Tokyo 102-8160 and Sandulescu, N. and Institute for Physics and Nuclear Engineering, P.O. Box MG-6, RO-76900 Bucharest and Van Giai, N.},
abstractNote = {Giant neutron halos in medium-heavy nuclei are studied in the framework of the Hartree-Fock-Bogoliubov (HFB) approach with Skyrme interactions. The appearance of such structures depends sensitively on the effective interaction adopted. This is illustrated by comparing the predictions of SLy4 and SkI4 in the Ca and Zr isotopic chains. The latter force predicts a neutron halo in the Zr chain with A>122 due to the weakly bound orbitals 3p1/2 and 3p3/2. It is found that the energies of states near the separation threshold depend sensitively on effective mass values. The structure of the halo is analyzed in terms of the occupation probabilities of these orbitals and their partial contributions to the neutron density. The antihalo effect is also discussed in the case of {sup 124}Zr by comparing the occupation probabilities and wave functions of the Hartree-Fock neutron single-particle states near the Fermi energy with the corresponding HFB quasiparticle states.},
doi = {10.1103/PHYSREVC.74.064317},
journal = {Physical Review. C, Nuclear Physics},
number = 6,
volume = 74,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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