Experimentally observed ground state band based on the 1/2-[521] Nilsson state and the first exited band based on the 7/2-[514] Nilsson state of the odd-Z nucleus 255Lr are studied by the cranked shell model （CSM） w...Experimentally observed ground state band based on the 1/2-[521] Nilsson state and the first exited band based on the 7/2-[514] Nilsson state of the odd-Z nucleus 255Lr are studied by the cranked shell model （CSM） with the paring correlations treated by the particle-number-conserving （PNC） method. This is the first time the detailed theoretical investigations are performed on these rotational bands. Both experimental kinematic and dynamic moments of inertia （f^（1） and ,f^（2） versus rotational frequency are reproduced quite well by the PNC-CSM calculations. By comparing the theoretical kinematic moment of inertia f（1） with the experimental ones extracted from different spin assignments, the spin 17/2- →13/2- is assigned to the lowest-lying 196.6（5） keV transition of the 1/2- [521 ] band, and 15/2→11/2- to the 189（1） keV transition of the 7/2- [514] band, respectively. The proton N = 7 major shell is included in the calculations. The intruder of the high-j low→lj15/2 （1/2-[770]） orbital at the high spin leads to band-crossings at hω = 0.20 （hω~=0.25） MeV for the 7/2-[514]ω= -1/2 （ω= ＋1/2） band, and at hω=0.175 MeV for the 1/2- [521 ] ω= - 1/2 band, respectively. Further investigations show that the band-crossing frequencies are quadrupole deformation dependent.展开更多
Based on the relativistic calculations of the nuclear masses in the transfermium region from No(Z=102)to Ds(Z=110)using the deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc),the possible existence of...Based on the relativistic calculations of the nuclear masses in the transfermium region from No(Z=102)to Ds(Z=110)using the deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc),the possible existence of bound nuclei beyond the neutron drip lines is studied.The two-neutron and multi-neutron emission bound nuclei beyond the primary neutron drip line of N=258 are predicted in Z=106,108,and 110 isotopes.A detailed microscopic mechanism investigation reveals that nuclear deformation plays a vital role in the existence of bound nuclei beyond the drip line.Furthermore,not only the quadrupole deformation β_(2) but also the higher orders of deformation are indispensable in the reliable description of the phenomenon of reentrant binding.展开更多
The multi-particle states and rotational properties of the two-particle bands in 254No are investigated by the cranked shell model with pairing correlations treated by the particle number conserving method. The rotati...The multi-particle states and rotational properties of the two-particle bands in 254No are investigated by the cranked shell model with pairing correlations treated by the particle number conserving method. The rotational bands on top of the two-particle Kπ= 3+, 8- and 10+ states and the pairing reduction are studied theoretically in 254No for the first time. The experimental excitation energies and moments of inertia of the multi-particle states are reproduced well by the calculations. Better agreement with the data is achieved by including the high-order deformation ε6,J（1） in these two-particle bands compared with the ground state band is attributed to the pairing reduction due to the Pauli blocking effect.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11275098 and 11275067)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Experimentally observed ground state band based on the 1/2-[521] Nilsson state and the first exited band based on the 7/2-[514] Nilsson state of the odd-Z nucleus 255Lr are studied by the cranked shell model （CSM） with the paring correlations treated by the particle-number-conserving （PNC） method. This is the first time the detailed theoretical investigations are performed on these rotational bands. Both experimental kinematic and dynamic moments of inertia （f^（1） and ,f^（2） versus rotational frequency are reproduced quite well by the PNC-CSM calculations. By comparing the theoretical kinematic moment of inertia f（1） with the experimental ones extracted from different spin assignments, the spin 17/2- →13/2- is assigned to the lowest-lying 196.6（5） keV transition of the 1/2- [521 ] band, and 15/2→11/2- to the 189（1） keV transition of the 7/2- [514] band, respectively. The proton N = 7 major shell is included in the calculations. The intruder of the high-j low→lj15/2 （1/2-[770]） orbital at the high spin leads to band-crossings at hω = 0.20 （hω~=0.25） MeV for the 7/2-[514]ω= -1/2 （ω= ＋1/2） band, and at hω=0.175 MeV for the 1/2- [521 ] ω= - 1/2 band, respectively. Further investigations show that the band-crossing frequencies are quadrupole deformation dependent.
基金Supported by the National Natural Science Foundation of China(U2032138,11775112,12075085,11935003,12047568,11790323,11790325)the State Key Laboratory of Nuclear Physics and Technology,Peking University(NPT2020ZZ01)。
文摘Based on the relativistic calculations of the nuclear masses in the transfermium region from No(Z=102)to Ds(Z=110)using the deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc),the possible existence of bound nuclei beyond the neutron drip lines is studied.The two-neutron and multi-neutron emission bound nuclei beyond the primary neutron drip line of N=258 are predicted in Z=106,108,and 110 isotopes.A detailed microscopic mechanism investigation reveals that nuclear deformation plays a vital role in the existence of bound nuclei beyond the drip line.Furthermore,not only the quadrupole deformation β_(2) but also the higher orders of deformation are indispensable in the reliable description of the phenomenon of reentrant binding.
基金Supported by the National Natural Science Foundation of China(11775112,11535004,11875027,11761161001)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The multi-particle states and rotational properties of the two-particle bands in 254No are investigated by the cranked shell model with pairing correlations treated by the particle number conserving method. The rotational bands on top of the two-particle Kπ= 3+, 8- and 10+ states and the pairing reduction are studied theoretically in 254No for the first time. The experimental excitation energies and moments of inertia of the multi-particle states are reproduced well by the calculations. Better agreement with the data is achieved by including the high-order deformation ε6,J（1） in these two-particle bands compared with the ground state band is attributed to the pairing reduction due to the Pauli blocking effect.
