The g-factors of the rotational states along the positive parity yrast band in even-even nuclei ^(84)Zr were measured up to a spin I=16^(+)by a transient magnetic field-ion implanted perturbed angular distribution met...The g-factors of the rotational states along the positive parity yrast band in even-even nuclei ^(84)Zr were measured up to a spin I=16^(+)by a transient magnetic field-ion implanted perturbed angular distribution method and calculated by a cranking shell model.A peak structure of the g-factors has been observed for the first time.The measured g-factors confirm the mixed configuration of proton and neutron alignments.展开更多
High spin states of the odd-proton nucleus ^(167)Lu have been studied via ^(152)Sm(^(19)F,4n)^(167)Lu reaction at 87MeV beam energy.A weakly populated new rotationa1 band has been observed and assigned as i13/2 proton...High spin states of the odd-proton nucleus ^(167)Lu have been studied via ^(152)Sm(^(19)F,4n)^(167)Lu reaction at 87MeV beam energy.A weakly populated new rotationa1 band has been observed and assigned as i13/2 proton 1/2^(+)[660] band.This new band and the 1/2^(+)[660] band in ^(171)Ta from the early work are classified as superdeformed bands with triaxiality.展开更多
The triaxially superdeformed states in 162Lu are investigated using the three-dimensional total routhian surface calculation, and the deformation parameters and the likely configuration are given. The shell and pairin...The triaxially superdeformed states in 162Lu are investigated using the three-dimensional total routhian surface calculation, and the deformation parameters and the likely configuration are given. The shell and pairing correction energies are considered respectively, and the formation mechanism of triaxial superdeformation is investigated.展开更多
The projected Woods-Saxon (WS) quasi-particle states have been used as the bases in the calculation of the reflection asymmetric shell model (RASM). The WS potential has been modified but constrained to give the simil...The projected Woods-Saxon (WS) quasi-particle states have been used as the bases in the calculation of the reflection asymmetric shell model (RASM). The WS potential has been modified but constrained to give the similar single-particle levels of the standard WS potential. Correspondingly, the multipole interactions in the total RASM Hamiltonian are constructed according to the modified WS potential. The calculated octupole band of 228Th from this approach is in good agreement with experimental data.展开更多
The Reflection Asymmetric Shell Model has been formulated to describe the high spin states of octupole deformed nuclei.The long-range separable forces of quadrupole,octupole and hexadecapole as well as monopole and qu...The Reflection Asymmetric Shell Model has been formulated to describe the high spin states of octupole deformed nuclei.The long-range separable forces of quadrupole,octupole and hexadecapole as well as monopole and quadrupole pairing are included in the Hamiltonian.The bases,on which the Hamiltonian is diagonalized,are the eigenstates of angular momentum and parity obtained by projecting the octupole deformed multi-quasiparticle states onto good angular momentum and good parity.The general features of rotational octupole bands in even-even nuclei can be reproduced by the model and the calculated result is in good agreement with experiment.展开更多
Two Garvey-Kelson mass relations are found to be directly related to the n-p interaction. In the case of the same nuclear core, the neutron-proton interaction energy between two neutrons and one proton ∈2n-1p is expe...Two Garvey-Kelson mass relations are found to be directly related to the n-p interaction. In the case of the same nuclear core, the neutron-proton interaction energy between two neutrons and one proton ∈2n-1p is experimentally found to be close to that between one neutron and two protons ∈1n-2p, which is equivalent to the first Garvey-Kelson mass relation. The sum of∈2n-1p and ∈1n-2p is close to the n-p interaction energy between two neutrons and two protons ∈2n-2p, which leads to the second Garvey-Kelson mass relation. An explanation of these two n-p interaction relations is presented. It is shown that both of these mass relations hold more accurately when the core is an even-even core.展开更多
The discovery of the triaxial superdeformed bands provide a new opportunity to understand the axial symmetry breaking even in highly elongated nuclei. A total of 17 triaxial superdeformed nuclei in the mass A ~ 160 re...The discovery of the triaxial superdeformed bands provide a new opportunity to understand the axial symmetry breaking even in highly elongated nuclei. A total of 17 triaxial superdeformed nuclei in the mass A ~ 160 region and 11 in the mass A ~ 80 region are predicted by the three dimensional total routhian surface calculations. A possible way to identify the triaxiality of triaxial superdeformed nuclei is suggested.展开更多
High spin states in neutron-deficient ^(117)Xe have been studied by using in-beamγspectroscopy method.A new positive-parity rotational band has been identified.It decays into the yrast vh_(11/2 )band via five electri...High spin states in neutron-deficient ^(117)Xe have been studied by using in-beamγspectroscopy method.A new positive-parity rotational band has been identified.It decays into the yrast vh_(11/2 )band via five electric dipole transitions.The magnitudes of these E1 transitions are extracted and they are much enhanced compared to the normal E1 transitions.This is taken as an evidence for octupole correlations in ^(117)Xe.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.19775070.
文摘The g-factors of the rotational states along the positive parity yrast band in even-even nuclei ^(84)Zr were measured up to a spin I=16^(+)by a transient magnetic field-ion implanted perturbed angular distribution method and calculated by a cranking shell model.A peak structure of the g-factors has been observed for the first time.The measured g-factors confirm the mixed configuration of proton and neutron alignments.
基金Supported by the National Natural Science Foundation of Chinathe Science Foundation of Nuclear Industry of China.
文摘High spin states of the odd-proton nucleus ^(167)Lu have been studied via ^(152)Sm(^(19)F,4n)^(167)Lu reaction at 87MeV beam energy.A weakly populated new rotationa1 band has been observed and assigned as i13/2 proton 1/2^(+)[660] band.This new band and the 1/2^(+)[660] band in ^(171)Ta from the early work are classified as superdeformed bands with triaxiality.
文摘The triaxially superdeformed states in 162Lu are investigated using the three-dimensional total routhian surface calculation, and the deformation parameters and the likely configuration are given. The shell and pairing correction energies are considered respectively, and the formation mechanism of triaxial superdeformation is investigated.
基金Supported in part by the Major State Basic Research Development Program under contract No.G2000077407the National Natural Science Foundation of China under Grant Nos.19935030 and 10075078。
文摘The projected Woods-Saxon (WS) quasi-particle states have been used as the bases in the calculation of the reflection asymmetric shell model (RASM). The WS potential has been modified but constrained to give the similar single-particle levels of the standard WS potential. Correspondingly, the multipole interactions in the total RASM Hamiltonian are constructed according to the modified WS potential. The calculated octupole band of 228Th from this approach is in good agreement with experimental data.
基金Supported in part by the Major State Basic Research Development Program under contract No.G2000077407the National Natural Science Foundation of China under Grant Nos.19935030 and 10075078.
文摘The Reflection Asymmetric Shell Model has been formulated to describe the high spin states of octupole deformed nuclei.The long-range separable forces of quadrupole,octupole and hexadecapole as well as monopole and quadrupole pairing are included in the Hamiltonian.The bases,on which the Hamiltonian is diagonalized,are the eigenstates of angular momentum and parity obtained by projecting the octupole deformed multi-quasiparticle states onto good angular momentum and good parity.The general features of rotational octupole bands in even-even nuclei can be reproduced by the model and the calculated result is in good agreement with experiment.
基金Supported in part by the Major State Basic Research Development Program under contract No.G2000077407the National Natural Science Foundation of China under Grant Nos.19935030 and 10075078.
文摘Two Garvey-Kelson mass relations are found to be directly related to the n-p interaction. In the case of the same nuclear core, the neutron-proton interaction energy between two neutrons and one proton ∈2n-1p is experimentally found to be close to that between one neutron and two protons ∈1n-2p, which is equivalent to the first Garvey-Kelson mass relation. The sum of∈2n-1p and ∈1n-2p is close to the n-p interaction energy between two neutrons and two protons ∈2n-2p, which leads to the second Garvey-Kelson mass relation. An explanation of these two n-p interaction relations is presented. It is shown that both of these mass relations hold more accurately when the core is an even-even core.
基金Supported by the National Natural Science Foundation of China under Grant Nos.19975062,19835010 and 19935030.
文摘The discovery of the triaxial superdeformed bands provide a new opportunity to understand the axial symmetry breaking even in highly elongated nuclei. A total of 17 triaxial superdeformed nuclei in the mass A ~ 160 region and 11 in the mass A ~ 80 region are predicted by the three dimensional total routhian surface calculations. A possible way to identify the triaxiality of triaxial superdeformed nuclei is suggested.
基金Supported by the National Natural Science Foundation of China。
文摘High spin states in neutron-deficient ^(117)Xe have been studied by using in-beamγspectroscopy method.A new positive-parity rotational band has been identified.It decays into the yrast vh_(11/2 )band via five electric dipole transitions.The magnitudes of these E1 transitions are extracted and they are much enhanced compared to the normal E1 transitions.This is taken as an evidence for octupole correlations in ^(117)Xe.
