The properties of nuclei belonging to the newly observed α-decay chain starting from ^265Bh have been studied. The axially deformed relativistic mean-field calculation with the force NL-Z2 has been performed in the b...The properties of nuclei belonging to the newly observed α-decay chain starting from ^265Bh have been studied. The axially deformed relativistic mean-field calculation with the force NL-Z2 has been performed in the blocked BCS approximation. Some ground state properties such as binding energies, deformations, spins, and parities, as well as Q-values of the a-decay for this decay chain have been calculated and compared with known experimentai data. Good agreement is found. The slngle-particle spectrum of the nucleus ^265Bh is studied and some new magic numbers are found, while the magnitudes of the shell gaps in superheavy nuclei are much smaller than those of nuclei before the actinium region, and the Fermi surfaces are close to the continuum. Thus the superheavy nuclei are usually not stable. The a-decay lifetimes in the ^265Bh decay chain are evaluated by different formulae, and compared with experimental data. The methods which give good agreement with the data are selected.展开更多
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10175082, 10235020, 10375001, 10275094, and 10075080, the Major Basic Research Development Program under Grant Nos. G2000-0774-07 and G2000-0774-00, the Knowledge Innovation Project of the Chinese Academy of Sciences under Grant No. KJCX2-SW-N02, 0ne Hundred" Person Project of CAS, the State Key Basic Research Program of the Ministry of Science and Technology under Grant Nos. 2001CCB01200 and 2002CCB00200
文摘The properties of nuclei belonging to the newly observed α-decay chain starting from ^265Bh have been studied. The axially deformed relativistic mean-field calculation with the force NL-Z2 has been performed in the blocked BCS approximation. Some ground state properties such as binding energies, deformations, spins, and parities, as well as Q-values of the a-decay for this decay chain have been calculated and compared with known experimentai data. Good agreement is found. The slngle-particle spectrum of the nucleus ^265Bh is studied and some new magic numbers are found, while the magnitudes of the shell gaps in superheavy nuclei are much smaller than those of nuclei before the actinium region, and the Fermi surfaces are close to the continuum. Thus the superheavy nuclei are usually not stable. The a-decay lifetimes in the ^265Bh decay chain are evaluated by different formulae, and compared with experimental data. The methods which give good agreement with the data are selected.