~(157)YB的形状共存和Vi_(13/2)带的结构演变

利用在束γ谱学技术,通过反应144Sm（16O,3n）研究了157Yb的高自旋态,其中16O束流的能量为90MeV.采用门套BGO（AC）HPGe探测器进行了长时间的γ-γ-t符合测量.基于γ-γ符合关系、γ射线的各向异性度和DCO系数的测量结果,首次建立了157Yb的高自旋能级纲图.围绕157Yb的能级纲图着重讨论了此核的形状共存和Vi13/2能带随着角动量增加的结构演变,另外还比较了N=87同中子素链的Vi13/2转动带结构的系统性.

缺中子核素~(129)Ce的(EC/β~+)衰变

利用 10 2MeV16O6+束轰击同位素靶117Sn ,通过熔合蒸发 4n反应产生核素12 9Ce.由氦喷嘴快速带传输系统将反应产物送到低本底区 .通过化学分离来制备待测的Ce样品 ,与此同时用16O束轰击117Sn的两种相邻的同位素靶118Sn和116Sn ,并比较上述 3种反应中的产物来进一步区分元素Ce的不同的同位素 .结果一种半衰期为 4.1min的活性被鉴定为12 9Ce.基于X -γ -t和γ -γ -t符合测量 ,建议了包括 5 1条射线在内的12 9Ce的 (EC/ β+)衰变纲图 .其中 ,12 9Ce基态直接馈送到12 9La基态的份额 ( 2 6± 7) %是用观测到的12 9La衰变的 2 78.6keV的γ射线的生长和衰变曲线估计出来的 .另外还给出了用La Kα X射线和6 8.2keVγ射线开门的γ谱以及典型的衰变γ射线的时间谱

~(206)At的[лh_(1/2)vi_(13/2)~(-1)]10~-同质异能态研究(英文)

利用能量为６０－８０ＭｅＶ的~(１２)Ｃ束流，通过~１９７Ａｎ（~(１２)Ｃ，３ｎ）~２０６Ａｔ反应研究了~２０６Ａｔ核的高自旋能级结构．用７台ＢＧＯ（ＡＣ）ＨＰＧｅ探测器和一台用于探测低能γ射线的平面型ＨＰＧｅ探测器进行了γ射线的激发函数、γ－γ－ｔ符合及γ射线的角分布测量．基于这些测量，首次建立了包括２５条γ跃迁的~２０６Ａｔ高自旋能级纲图．确定了一个半寿命为（９０８±４００）ｎｓ、自旋和宇称为１０的同质异能态．基于较重的双奇核~(２０８，２１０ )Ａｔ能级结构的系统性，对~(２０６)Ａｔ的１０~－同质异能态进行了讨论．

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.

X-ray spectra induced by Xe-129(q+) impacting the metal surface

Using the slow highly charged ions Xe-129(q+) (q = 25, 26, 27; initial kinetic T-0 <= 4.65 keV/a.u.) to impact Au surface, the Au atomic M alpha characteristic X-ray spectrum is induced. The result shows that as long as the charge state of projectile is high enough, the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak (nA magnitude), and the X-ray yield per ion is in the order of 10(-8) and increases with the kinetic energy and potential energy of projectile. By measuring the Au M alpha-X-ray spectra, Au atomic N-level lifetime is estimated at about 1.33x10(-18) s based on Heisenberg uncertainty relation.