NUCLEAR SHAPE PROPERTIES OF THE EVEN–EVEN NEUTRON-RICH RARE-EARTH NUCLEI

The physical properties of the nuclear shape have been investigated through the charge square radius (<r2>) and the quadrupole (Q2) and hexadecapole (Q4) moments of the even–even neutron-rich rare-earth nuclei. The single-particle energies used are those of a deformed Woods–Saxon mean-field. The pairing effects have been included by means of an exact projection method. The model has been tested for the "ordinary" nuclei near the shell closure N = 82 and has correctly reproduced the experimental data and particularly the "Kink" effect. The study has then been extended to the neutron-rich nuclei and has shown a stability of the <r2> and Q2 results for N≃100 which may be attributed to the existence of a new magic number. On the other hand, a saturation of the prolate shape appears around N = 108 for the elements Nd , Sm and Gd and near N = 102 for the Dy , Er and Yb . These observations could not be confirmed by the investigation of the hexadecapole moment.

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Implications of occupancy of 2s1/2 state in sd-shell within RMF+BCS approach

International Journal of Modern Physics E ◽

10.1142/s0218301317500720 ◽

2017 ◽

Vol 26 (11) ◽

pp. 1750072 ◽

Cited By ~ 11

Author(s):

G. Saxena ◽

M. Kumawat ◽

M. Kaushik ◽

U. K. Singh ◽

S. K. Jain ◽

...

Keyword(s):

Mean Field ◽

The Other ◽

Magic Numbers ◽

Neutron Density ◽

Shell Closure ◽

Weakly Bound ◽

Density Profiles ◽

Relativistic Mean Field ◽

Structure Formula ◽

Bubble Structure

We employ the relativistic mean-field plus BCS (RMF+BCS) approach to study the behavior of [Formula: see text]-shell by investigating in detail the single particle energies, and proton and neutron density profiles along with the deformations and radii of even–even nuclei. Emergence of new shell closure, weakly bound structure and most recent phenomenon of bubble structure are reported in the [Formula: see text]-shell. [Formula: see text]C, [Formula: see text]O and [Formula: see text]S are found to have a weakly bound structure due to particle occupancy in 2[Formula: see text] state. On the other hand [Formula: see text]O, [Formula: see text]Ca and [Formula: see text]Si are found with depleted central density due to the unoccupied 2[Formula: see text] state and hence they are the potential candidates of bubble structure. [Formula: see text]C and [Formula: see text]O emerge as doubly magic with [Formula: see text] in accord with the recent experiments and [Formula: see text]S emerges as a new proton magic nucleus with [Formula: see text]. [Formula: see text] and [Formula: see text] are predicted as magic numbers in doubly magic [Formula: see text]O, [Formula: see text]Ca and [Formula: see text]Si, respectively. These results are found in agreement with the recent experiments and have consistent with the other parameters of RMF and other theories.

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Nuclear spin scissors mode – experimental status

EPJ Web of Conferences ◽

10.1051/epjconf/201819404004 ◽

2018 ◽

Vol 194 ◽

pp. 04004

Author(s):

Irina Molodtsova ◽

Evgeny Balbutsev ◽

Peter Schuck

Keyword(s):

Experimental Data ◽

Rare Earth ◽

Nuclear Spin ◽

Collective Motion ◽

Systematic Analysis ◽

Scissors Mode ◽

Experimental Status ◽

Rare Earth Nuclei ◽

New Type

A new type of nuclear collective motion - the spin scissors mode - was predicted seven years ago. Promising signs of its existence in 232Th were found. We perform a systematic analysis of experimental data on M1 excitations in rare-earth nuclei to find traces of the spin scissors mode in this area. Obvious signs of its existence are demonstrated.

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Nuclear Shape Transitions and Some Properties of Aligned-Particle Configurations at Very High Spin in Some Rare-Earth Nuclei

Annalen der Physik ◽

10.1002/andp.19905020108 ◽

1990 ◽

Vol 502 (1) ◽

pp. 68-80 ◽

Cited By ~ 1

Author(s):

N. Mansour ◽

T. Bayomy ◽

Z. Awwad

Keyword(s):

Rare Earth ◽

High Spin ◽

Nuclear Shape ◽

Rare Earth Nuclei ◽

Very High ◽

Shape Transitions

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THE ORIGIN OF NUCLEAR SHAPE TRANSITIONS

Modern Physics Letters A ◽

10.1142/s0217732393002671 ◽

1993 ◽

Vol 08 (13) ◽

pp. 1185-1189 ◽

Cited By ~ 4

Author(s):

G. D. YEN ◽

H. G. MILLER ◽

R. M. QUICK

Keyword(s):

Nuclear Energy ◽

Mean Field ◽

Closed Shell ◽

Quadrupole Deformation ◽

Spherical Nucleus ◽

Nuclear Shape ◽

Energy Spectra ◽

Deformed Nuclei ◽

Deformation Parameters ◽

Rare Earth Nuclei

The experimental nuclear energy spectra indicate the rare-earth nuclei undergo a collective-to-noncollective transition even for a closed-shell spherical nucleus. For off-shell deformed nuclei this transition may be accompanied by a change in the nuclear shape in finite temperature mean field theories which is not seen in exact canonical calculations. Therefore, a theory using the quadrupole deformation parameters β and γ as the order parameter for this transition may be misleading.

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