Krane K S
Department of Physics, Oregon State University, Corvallis, OR 97331, USA.
Appl Radiat Isot. 2015 Mar;97:12-20. doi: 10.1016/j.apradiso.2014.12.006. Epub 2014 Dec 6.
High-resolution γ ray spectroscopy experiments have been done to study the emissions from the radioactive decay of 22-min (83g)Se produced from neutron capture using samples of enriched (82)Se. Energy and intensity values have been obtained to roughly an order of magnitude greater precision than in previous studies. Based on energy sums, 2 new levels are proposed in the daughter (83)Br and one previously proposed level is shown to be doubtful. Some 25 new transitions appear to decay with the (83)Se halflife, about half of which can be accommodated among the previous or newly proposed levels. Several previous γ ray placements are shown to be inconsistent with the new determinations of the (83)Br energy levels, but cannot be accommodated anywhere else among the known levels. As a result of the missing γ ray placements, some of the β branchings in the decay to levels of (83)Br appear to be negative. Gamma rays from the 2.4-h decay of the daughter (83)Br to levels of (83)Kr have also been observed, along with decays of (81g)(,m)Se present as a small impurity in the enriched samples and also as a strong component in irradiated samples of natural Se.
已开展高分辨率γ射线能谱实验，以研究使用富集（82）Se样本通过中子俘获产生的22分钟（83g）Se放射性衰变所发出的射线。所获得的能量和强度值的精度比以往研究提高了大约一个数量级。基于能量总和，在子核（83）Br中提出了2个新能级，并且表明之前提出的一个能级存在疑问。约25条新跃迁似乎以（83）Se半衰期衰变，其中约一半可归入先前或新提出的能级中。先前的一些γ射线位置显示与（83）Br能级的新测定结果不一致，但在已知能级中的其他任何地方都无法安置。由于γ射线位置缺失，衰变至（83）Br能级时的一些β分支似乎为负。还观测到了子核（83）Br到（83）Kr能级的2.4小时衰变所产生的γ射线，以及作为富集样本中的少量杂质以及天然Se辐照样本中的强成分存在的（81g），mSe的衰变。
