High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3/2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3/2-[521] band.
CHEN Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3 & ZHU LiHua4 1Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
The evaporation residue cross sections of synthesizing superheavy nuclei Z=119, 120 are calculated by different sets of master equations with different dynamical variables. Two methods basically predicted similar results that the Ca induced hot fusion can 48 produce element 119 easier than produce 120, and the evaporation residue cross sections for 119 are detectable by current advanced techniques, while the evaporation residue cross sections are below 0.1 pb for producing element 120.
GAN ZaiGuo1, ZHOU XiaoHong1, HUANG MingHui1, FENG ZhaoQing1 & LI JunQing1,2 1Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
A new rotational band has been identified and assigned to 188Au for the first time using the 173Yb(19F,4nγ) reaction at the beam energies of 86 and 90 MeV. This band is proposed to be built on the πh9/2 νi13/2 configuration by comparing the band properties with known bands in neighboring nuclei. The prolate-to-oblate shape transition through triaxial shape has been proposed to occur around 188Au for the πh9/2 νi13/2 bands in odd-odd Au isotopes on the basis of total Routhian surface (TRS) calculations.
OSHIMA MTOH YKOIZUMI MKIMURA AHatsukawa YMORIKAWA TNAKAMURA MSUGAWARE MKUSAKARI H
Theoretical calculations have been performed for the ν9/2+[624](i13/2) and ν7/2-[503](f7/2) bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2+[624](i13/2) component, while the negative-parity band shows strong mixing of ν7/2-[503](f7/2) and ν9/2-[505](h9/2) configurations.
LI GuangShun1,2, ZHOU XiaoHong1,2, ZHANG ShuangQuan3, ZHANG YuHu1 & MENG Jie3 1 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
High-spin states in 185Pt have been reinvestigated via the reaction 173Yb(16O, 4n) at a beam energy of 90 MeV. The previously known band based on the ν7/2-[503](f7/2) Nilsson orbital has been extended to higher spin states. Properties of the ν7/2-[503](f7/2) band have been discussed with an emphasis on the evolution of configuration while increasing the spin.
李广顺周小红张玉虎周厚兵滑伟王世陶丁兵王海霞Oshima MToh YKoizumi MOsa AHatsukawa YSugawara M
High-spin levels of 189Pt have been studied with the in-beam γ-spectroscopy method via the 176Yb(18O,5n) reaction at the beam energies of 88 and 95 MeV. The previously known νi-131/2 band has been confirmed, and its unfavored signature branch extended up to the 13/2+ state. Within the framework of the triaxial particle-rotor model, the νi-113/2 band is suggested to be associated with the 11/2[615] configuration, and to have triaxial deformation.
滑伟周小红张玉虎郭应祥Oshima M.Toh Y.Koizumi M.Osa A.Hatsukawa Y.亓斌张双全孟杰Sugawara M.
High-spin states in nucleus 139Pm have been studied using the reaction 116Cd(27Al,4n)139Pm.Two dipole cascades have been found.Spin and parity assignments were based on the Directional Correlation of Oriented Nuclei(DCO) ratios and systematic behavior in neighboring odd-proton nuclei.The level structures of 139Pm are compared with those of the N =78 isotone 141Eu in which two dipole bands have been confirmed as magnetic rotational bands.The close similarity between them suggests that the dipole bands in 139Pm may be magnetic rotational bands.
