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Theoretical calculations have been performed for the ν9/2+[624](i 13/2) and ν7/2−[503]( f 7/2) 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 proposed to be dominated by the ν9/2+[624](i 13/2) component, while the negative-parity band shows strong mixing of ν7/2−[503](f 7/2) and ν9/2−[505](h 9/2) configurations.

High-spin states in 161Er have been studied experimentally using the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. The relatively enhanced E1 transitions between the 5/2+[642] and 3/2−[521] bands are observed in 161Er, and the B(E1) values are extracted experimentally. The systematics of the R(E1) values in the N = 93 isotones are presented. It is found that the strength of the E1 transitions obviously exhibits angular momentum dependence, and the occurrence of the relatively enhanced E1 transitions could be attributed to octupole softness.

The complete fusion reaction 40 Ca+ 175 Lu was studied at a beam energy of 5.1 MeV u �1 . Evaporation residues recoiled from the target were separated from the primary beam by the gas-filled recoil separator SHANS and then implanted into the focal plane detection system. Based on the energy-positiontime correlation measurement, neutron-deficient nuclei − 208 213 Ac, 212 Pa and 211 Th produced in this reaction were identified. Previously reported decay properties of the ground state in 212 Pa were confirmed and improved values of − + 5.1 1.7 ms and 8.250(20) MeV for the half-life and α-particle energy of 212 Pa were obtained. No correlated decay chain arising from 211 Pa was observed and an upper limit for the cross section of 211 Pa was estimated.

A gas-filled recoil separator was designed and built newly at Institute of Modern Physics (IMP) in Lanzhou. With the recent commissioning of the separator, the decay properties of 271Ds were studied via the 208Pb (64Ni, n) reaction at a beam energy of 313.3 MeV. One α-decay chain for 271Ds was established in total. The experimental result is consistent with the values reported in the literature.

The high-spin level structure of 186Au is re-investigated by means of in-beam γ-ray spectroscopy via the 172Yb(19F, 5nγ)186Au reaction. The oblate bands previously reported are revised and extended to higher-spin states. A new Iπ = (20+) excited state has been identified and assigned to the πh−111/2 ⊗ νi−213/2h−19/2 configuration. The total Routhian surface and cranked shell model calculations suggest that the πh−111/2 ⊗ νi−213/2h−19/2 band in 186Au has a non-axial deformation.

With the recent commissioning of a gas-filled recoil separator at Institute of Modern Physics (IMP) in Lanzhou, the decay properties of (271)Ds (Z = 110) were studied via the Pb-208(Ni-64, n) reaction at a beam energy of 313.3MeV. Based on the separator coupled with a position sensitive silicon strip detector, we carried out the energy-position-time correlation measurements for the implanted nucleus and its subsequent decay alpha's. One alpha-decay chain for (271)Ds was established. The.. energy and decay time of the (271)Ds nucleus were measured to be 10.644 MeV and 96.8 ms, which are consistent with the values reported in the literature.

High-spin states in 185Pt have been investigated using the 173Yb(16O, 4n) reaction at a beam energy of 90 MeV. The 7/2?[503] band in 185Pt is revised, and particularly the intra-band B(M1)/B(E2) ratios are deduced experimentally. Low-spin signature inversion is revealed in the 7/2?[503] band. The signature inversion can be interpreted if we assume configuration change in this band from the 7/2?[503] orbital to the 7/2?[514] orbital with increasing spin, which is supported by comparing the measured B(M1)/B(E2) ratios with the theoretical values from the semi-classical D?nau and Frauendorf approach.