Determination of

The activity concentrations of 226Ra, 232Th, 40K and 235U in soil samples from a bauxite ore deposit site in Western Cameroon were determined by gamma spectrometry using a Broad-Energy Germanium (BEGe6350) detector. The average activity concentrations of 226Ra, 232Th, 40K and 235U were found to be 124.8 ± 58.1, 157.3 ± 67.3, 670.9 ± 272.3 and 5.8 ± 2.7 Bq kg-1, respectively. The measured activity concentrations of 226Ra, 232Th and 40K were compared with available data in some countries and the world average activity concentration of soil. The radiological hazard indices of radioactivity were calculated, with average values of 416.90 Bq kg-1 for the radium equivalent activity, 188.20 nGy h-1 for the gamma radiation dose rate, 0.23 mSv y-1 for the external outdoor annual effective dose, 0.92 mSv y-1 for the indoor annual effective dose, 1.02 mSv y-1 for the total annual effective dose and 1.13 for the external hazard index, respectively. These radiological hazard index values were also compared with the internationally approved values. Consequently, use of concrete bricks made of soil as building materials might lead to an increased radiation risk for the population of Fongo-Tongo

Observation of a pi h(9/2) circle times nu i(13/2) oblate band in Tl-188

Excited states in Tl-188 have been studied experimentally using the Gd-157(Cl-35;4n) reaction at a beam energy of 170 MeV. A rotational band built on the pi h(9/2) x nu i(13/2) configuration with oblate deformation has been established for Tl-188. Based on the structure systematics of the oblate pi h(9/2) x nu i(13/2) bands in the heavier odd-odd Tl nuclei, we have tentatively proposed spin values for the new band in Tl-188. The pi h(9/2) x nu i(13/2) oblate band in Tl-188 shows low-spin signature inversion, and it can be interpreted qualitatively by the two-quasiparticle plus rotor model including a J-dependent p-n residual interaction

Observation of a πh

Excited states in 188Tl have been studied experimentally using the 157Gd (35Cl, 4n) reaction at a beam energy of 170MeV. A rotational band built on the πh 9/2 ⊗ νi 13/2 configuration with oblate deformation has been established for 188Tl. Based on the structure systematics of the oblate πh 9/2 ⊗ νi 13/2 bands in the heavier odd-odd Tl nuclei, we have tentatively proposed spin values for the new band in 188Tl. The πh 9/2 ⊗ νi 13/2 oblate band in 188Tl shows low-spin signature inversion, and it can be interpreted qualitatively by the two-quasiparticle plus rotor model including a J-dependent p-n residual interaction

奇奇核~(90)Nb的高自旋态研究

用能量为80MeV的19F束通过反应76Ge(19F,5n)90Nb布居了90Nb的高自旋态.通过在束γ测量分析90Nb退激γ射线的符合级联关系,发现了19条新的属于90Nb的γ跃迁,建立了90Nb的高自旋态能级纲图.通过经验壳模型计算指定了部分能级的组态,并结合实验DCO比值和与相邻N=49核素的系统比较,确认了新能级的自旋和宇称

Search for signature inversion in the pi i(13/2) circle times upsilon i1(3/2) bands in Au-182,Au-184,Au-186

Search for low-spin signature inversion in the pi i(13/2) circle times nu i(13/2) bands in odd-odd Au-182,Au-184,Au-186 has been conducted through the standard in-beam gamma-spectroscopy techniques. The experiments for Au-182 and 186Au have been performed in the Japan Atomic Energy Agency (JAEA) via the Sm-152(Cl-35,5n)Au-182 and Yb-172(F-19,5n)Au-186 reactions, respectively. A study of Au-184 has been made using a multi-detector array GASP in LNL, Italy, via the Tb-159(Si-29,4n)Au-184 reaction. The pi i(13/2) circle times nu i(13/2) bands in these three nuclei have been identified and extended up to high-spin states. In particular, the inter-band connection between the pi i(13/2) nu i(13/2) band and the ground-state band in 184 Au has been established, leading to a firm spin-and-parity assignment for the pi i(13/2) circle times nu i(13/2) band. The low-spin signature inversion is found in the pi i(13/2) circle times nu i(13/2) bands in Au-182,Au-184,Au-186 according to our spin-assignment and the signature crossing observed at high-spin states

Search for signature inversion in the pi i(13/2)circle times nu i(13/2) bands in Au-182,Au-184,Au-186

Search for low-spin signature inversion in the pi i(13/2) circle times nu i(13/2) bands in odd-odd Au-182,Au-184,Au-186 has been conducted through the standard in-beam gamma-spectroscopy techniques via the Sm-152(Cl-35,5n) Au-182, Yb-172(F-19,5n) (186)An, and Tb-159(Si-29,4n) (184)An reactions, respectively. The pi i(13/2) circle times nu i(13/2) bands in these three nuclei have been identified and extended up to high-spin states. In particular, the inter-band connection between the pi i(13/2) circle times nu i(13/2) band and the ground-state band in Au-184 has been established, leading to a firm spin-and-parity assignment for the pi i(13/2) circle times nu i(13/2) band. The low-spin signature inversion is found in the pi i(13/2) circle times nu i(13/2) bands according to our spin-assignment and-the signature crossing observed at high-spin states