Masses, Deformations and Charge Radii--Nuclear Ground-State Properties in the Relativistic Mean Field Model

Use of the NL-SH parameter set is re-analyzed and a new parameter set TM2 is used for the first time in the axially deformed self-consistent relativistic mean-field calculations for 44 S and its neighboring nuclei 40 Mg and 42 Si . The spherical shell gap at N=28 in 44 S is found to be intact for the TM2 parameter set since it predicts the ground state of 44 S as nearly spherical, irrespective of the strength of the pairing force. The predictions of the NL-SH parameter set for 44 S are found to depend strongly on the pairing strength and, due to shape coexistence, the ground state could be strongly prolate or strongly oblate deformed. Hence, for the NL-SH parameter set, the spherical shell gap at N=28 in 44 S is broken for either of the prolate/oblate deformation. For 40 Mg and 42 Si , the spherical shell gap at N=28 is found broken under all conditions since the predicted deformations are large, independent of both the pairing strength and the choice of parameter set. This calls for immediate measurements of the deformations of these nuclei, particularly for 44 S which will decide its shell structure as well as the region of deformation in light nuclei.

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THE ROLE OF PION ON NUCLEI WITH CHARGE AND PARITY PROJECTED CHIRAL MEAN FIELD MODEL

Modern Physics Letters A ◽

10.1142/s021773230802985x ◽

2008 ◽

Vol 23 (27n30) ◽

pp. 2585-2588

Author(s):

YOKO OGAWA ◽

HIROSHI TOKI ◽

SETSUO TAMENAGA ◽

AKIHIRO HAGA

Keyword(s):

Ground State ◽

Field Model ◽

Mean Field ◽

High Momentum ◽

Mean Field Model ◽

Nuclear Ground State ◽

Pion Contribution ◽

Finite Nuclei ◽

Relativistic Framework

We construct a relativistic framework, charge and parity projected chiral mean field model, which takes into account explicitly a pion-exchange interaction. We take the chiral σ model Lagrangian for the construction of finite nuclei. We discuss several essential points of this framework with respect to explicit description of pionic-correlations, especially high-momentum component, in nuclear ground state wave function. We apply this framework to several even-even nuclei. We found that the pion contribution brings a significant change for nuclear ground state. We found that pion plays a role on the formation of jj-magic structure.

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EVOLUTION OF SHELL STRUCTURE IN NUCLEI

International Journal of Modern Physics E ◽

10.1142/s0218301311019581 ◽

2011 ◽

Vol 20 (08) ◽

pp. 1663-1675 ◽

Cited By ~ 4

Author(s):

A. BHAGWAT ◽

Y. K. GAMBHIR

Keyword(s):

Shell Structure ◽

Crucial Role ◽

Field Model ◽

Mean Field ◽

Mass Region ◽

The Other ◽

Mean Field Model ◽

Relativistic Mean Field ◽

Shell Closures ◽

Low Mass

Systematic investigations of the pairing and two-neutron separation energies which play a crucial role in the evolution of shell structure in nuclei, are carried out within the framework of relativistic mean-field model. The shell closures are found to be robust, as expected, up to the lead region. New shell closures appear in low mass region. In the superheavy region, on the other hand, it is found that the shell closures are not as robust, and they depend on the particular combinations of neutron and proton numbers. Effect of deformation on the shell structure is found to be marginal.

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TABLE OF GROUND STATE PROPERTIES OF NUCLEI IN THE RMF MODEL

Modern Physics Letters A ◽

10.1142/s0217732313500685 ◽

2013 ◽

Vol 28 (16) ◽

pp. 1350068 ◽

Cited By ~ 7

Author(s):

TUNCAY BAYRAM ◽

A. HAKAN YILMAZ

Keyword(s):

Ground State ◽

Mean Field ◽

Properties Of Nuclei ◽

Relativistic Mean Field ◽

Ground State Properties ◽

Pairing Correlations ◽

Ground State Energies ◽

Rmf Model

The ground state energies, sizes and deformations of 1897 even–even nuclei with 10≤Z ≤110 have been carried out by using the Relativistic Mean Field (RMF) model. In the present calculations, the nonlinear RMF force NL3* recent refitted version of the NL3 force has been used. The BCS (Bardeen–Cooper–Schrieffer) formalism with constant gap approximation has been taken into account for pairing correlations. The predictions of RMF model for the ground state properties of some nuclei have been discussed in detail.

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