Wu Xiao-Guang

Structure of the Semi-decoupled 1/2[411] Band in Odd Proton Nucleus169Ta

High spin states of the odd proton-nucleus 169Ta have been populated in the reaction 155Gd(19F,5n) with beam energies of 97 MeV. Rotational band based on d3/2 proton 1/2[411] Nilsson state has been pushed up to 39/2+ in the α = 1/2 decay sequence. Its signature partner, the α = -1/2 decay sequence with four link transitions has been established and 1/2[411] band in 169Ta was reassigned to be a semi-decoupled band. The systematics of the signature splitting in the K = 1/2 bands in the rear-earth region and the accidental degeneracy conclusion given by the angular projection shell model were discussed.

Proposed Chiral Doublet Bands in 98Tc

High spin states in odd-odd98 Tc nuclei are studied by in-beam γ-ray spectroscopy with the 96Zr(6Li, 4n) fusion-evaporation reaction at a beam energy of 35 MeV. The previous level scheme is updated. A band based on 1090.7 keV is expanded, and another band based on 1920.6 keV is newly identified. The observed two negative parity bands in 98Tc are proposed to be a pair of chiral doublet bands with the configuration πg9/2 ⊗ νh11/2. The evidence supporting the assignment of the chiral doublet bands is discussed. Signature splitting and signature inversion are observed in the πg9/2 ⊗ νh11/2 band in 98Tc.

Self-pumped phase conjugation in (K0.5Na0.5)2y (Sr0.61Ba0.39)1-yNb2O6 at 633nm

Self-pumped phase conjugation has been observed in Ce-doped (K0.5Nb0.5)2y (Sr0.61Ba0.39)1-yNb2O6 (KNSBN) crystal at 633nm by using He-Ne laser. The phase conjugate reflectivity as high as 40% was measured. The reflectivity as function of incident angles and the relation of response time to the incident intensities were studied experimentally.

Lifetime measurements in chiral nucleus 130Cs

The level lifetimes in partner bands of 130Cs have been measured using the Doppler Shift Attenuation method. The high-spin states of 130Cs were populated via fusion evaporation reaction 124Sn(11B,5n)130Cs at a beam energy of 65 MeV. The absolute M1 and E2 transition probabilities have been deduced. The results indicate that the partner bands of 130Cs manifest the chiral properties.

Electromagnetic Transition Strengths and New Insight into the Chirality in 106Ag

Excited states in 106Ag are populated through the heavy-ion fusion evaporation reaction 100Mo(11 B,5n)106 Ag at a beam energy of 60 MeV. Lifetimes are measured for transitions of the two negative-parity rotational bands in the nucleus 106 Ag. The reduced transition probabilities show a great difference between the two bands. The staggering of the B(M1) and B(M1)/B(E2) values with spin are not observed. The bands are identified to be built on two distinct quasiparticle configurations. These results are contrary to an earlier suggestion that the pair of bands in 106 Ag are chiral doublet bands.

Quest for Chirality in 107 Ag

High spin states in 107Ag have been studied via the 100Mo(11B, 4n)107Ag reaction at a beam energy of 60 MeV on the HI-13 tandem accelerator at the China Institute of Atomic Energy. By analyzing the gamma-gamma coincidence and their DCO ratios, a new level scheme of 107Ag is presented. The structures for the newly constructed bands are briefly discussed and tentatively assigned to be chiral doublet bands.

New band structures in 107Ag

High spin states in 107Ag are studied via the 100Mo(11B, 4n)107 Ag reaction at an incident beam energy of 60 MeV. Prompt γ-γ coincidence and DCO ratios are measured by the detector arrays in CIAE. The level scheme has been updated and a new negative band belonging to 107Ag is identified. The new negative side band has been constructed and its configuration is tentatively assigned to πg9/2 ⊗ νh11/2(g7/2/d5/2).

Measurements of g-Factor of Rotational Levels in 83Y

The g-factors of the positive parity rotational levels up to spin I = 41/2+ in 83Y have been measured by a transient-magnetic-field ion implantation perturbed angular distribution method. The experimentally measured g-factors show the g9/2 proton alignment followed by the g9/2 neutron alignment. The measured g-factors are in good agreement with the results calculated by an empirical formula based on the cranking shell model.

Band crossings and signature splitting in 159Ho

High spin states in 159 Ho were populated in the reaction 152 Sm(11 B,4n) at 60 MeV. The rotational band based on the 7/2+ [404] Nilsson configuration has been established and the rotational bands based on the 7/2- [523], 1/2+ [411] and 1/2- [541] Nilsson configurations have been extended. The neutron band crossings of the various bands and the energy signature splitting of the 7/2- [523] bands are analysed in terms of the cranked shell model.

Rotational State g-Factors in 84Zr

The g-factors of the rotational states along the positive parity yrast band in even-even nuclei 84Zr 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.