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Title: Doublet bands in {sup 126}Cs in the triaxial rotor model coupled with two quasiparticles

Abstract

The positive-parity doublet bands based on the {pi}h{sub 11/2}(multiply-in-circle sign){nu}h{sub 11/2} configuration in {sup 126}Cs were investigated in the two quasiparticles coupled with a triaxial rotor model. The energy spectra E(I), energy staggering parameter S(I)=[E(I)-E(I-1)]/2I,B(M1) and B(E2) values, intraband B(M1)/B(E2) ratios, B(M1){sub in}/B(M1){sub out} ratios, and orientation of the angular momentum for the rotor as well as the valence proton and neutron are calculated. After including the pairing correlation, good agreement has been obtained between the calculated results and the data available, which supports the interpretation of this positive-parity doublet bands as chiral bands.

Authors:
;  [1];  [1];  [2];  [1];  [2];  [2]
  1. School of Physics, MOE Key Laboratory of Heavy Ion Physics, Peking University, Beijing 100871 (China)
  2. (China)
Publication Date:
OSTI Identifier:
20991010
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevC.75.024309; (c) 2007 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; ANGULAR MOMENTUM; CESIUM 126; CHIRALITY; COLLECTIVE MODEL; ENERGY SPECTRA; MASS NUMBER; NEUTRONS; PARITY; PROTONS; QUASI PARTICLES; ROTORS

Citation Formats

Wang, S. Y., Qi, B., Zhang, S. Q., Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080, Meng, J., Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080, and Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000. Doublet bands in {sup 126}Cs in the triaxial rotor model coupled with two quasiparticles. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.024309.
Wang, S. Y., Qi, B., Zhang, S. Q., Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080, Meng, J., Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080, & Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000. Doublet bands in {sup 126}Cs in the triaxial rotor model coupled with two quasiparticles. United States. doi:10.1103/PHYSREVC.75.024309.
Wang, S. Y., Qi, B., Zhang, S. Q., Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080, Meng, J., Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080, and Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000. Thu . "Doublet bands in {sup 126}Cs in the triaxial rotor model coupled with two quasiparticles". United States. doi:10.1103/PHYSREVC.75.024309.
@article{osti_20991010,
title = {Doublet bands in {sup 126}Cs in the triaxial rotor model coupled with two quasiparticles},
author = {Wang, S. Y. and Qi, B. and Zhang, S. Q. and Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080 and Meng, J. and Institute of Theoretical Physics, Chinese Academy of Science, Beijing 100080 and Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000},
abstractNote = {The positive-parity doublet bands based on the {pi}h{sub 11/2}(multiply-in-circle sign){nu}h{sub 11/2} configuration in {sup 126}Cs were investigated in the two quasiparticles coupled with a triaxial rotor model. The energy spectra E(I), energy staggering parameter S(I)=[E(I)-E(I-1)]/2I,B(M1) and B(E2) values, intraband B(M1)/B(E2) ratios, B(M1){sub in}/B(M1){sub out} ratios, and orientation of the angular momentum for the rotor as well as the valence proton and neutron are calculated. After including the pairing correlation, good agreement has been obtained between the calculated results and the data available, which supports the interpretation of this positive-parity doublet bands as chiral bands.},
doi = {10.1103/PHYSREVC.75.024309},
journal = {Physical Review. C, Nuclear Physics},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
  • By taking the particle-triaxial-rotor model with variable moment of inertia, we systematically investigate the energy spectra, deformations, and single-particle configurations of the nuclei {sup 183,185,187}Tl. The calculated energy spectra agree quite well with experimental data. The obtained results indicate that the rotation-aligned bands observed in {sup 183,185,187}Tl originate from one of the [530](1/2){sup -},[532](3/2){sup -},[660](1/2){sup +} proton configurations coupled to a prolate deformed core. Furthermore, the negative parity bands built upon the (9/2){sup -} isomeric states in {sup 183,185,187}Tl are formed by a proton with the [505](9/2){sup -} configuration coupled to a core with triaxial oblate deformation, and the positivemore » parity band on the (13/2){sup +} isomeric state in {sup 187}Tl is generated by a proton with configuration [606](13/2){sup +} coupled to a triaxial oblate core.« less
  • A particle rotor model (PRM) with a quasi-proton and a quasi-neutron coupled with a triaxial rotor is developed and applied to study chiral doublet bands with configurations of an h{sub 11/2} proton and an h{sub 11/2} quasi-neutron. With pairing treated by the BCS approximation, the present quasiparticle PRM is aimed at simulating one proton and many neutron holes coupled with a triaxial rotor. After a detailed analysis of the angular momentum orientations, energy separation between the partner bands, and behavior of electromagnetic transitions, for the first time we find aplanar rotation or equivalently chiral geometry beyond the usual one protonmore » and one neutron hole coupled with a triaxial rotor.« less
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  • Carrying out particle-rotor model calculations, we have studied how stable the intrinsic structures of the K{sup {pi}}=1{sup +},I=1 states of two unique-parity, high-j quasiparticles are when the total spin is increased. We have found that the effect of the rotational perturbation is so large in high-j 2qp configurations that no rotational bands develop on most of them. This result is at variance with the previously suggested configuration for a rotational band in {sup 164}Dy. {copyright} {ital 1997} {ital The American Physical Society}
  • Coulomb excitation of states in /sup 193/Ir up to J = (21/2) has been observed with 160-MeV /sup 40/Ar and 617-MeV /sup 136/Xe ions. Most of these states are grouped into three rotational-like bands based on the (3/2)/sup +/ ground state, the (1/2)/sup +/ first excited state, and the (7/2)/sup +/ ..gamma..-vibrational-like state at 621 keV. The average deviation between experimental and theoretical energies for 18 states is 54 keV for the particle-asymmetric-rigid-rotor model and 66 keV for the interacting boson-fermion approximation model (limited to broken Spin(6) symmetry and only the d/sub 3/2/ orbital is considered). The overall agreement ofmore » both model predictions with experimental ..gamma..-ray yields for the collective transitions within the (3/2)/sup +/ band is quite good.« less