~(230)Ac的β延发裂变

详细信息

β-DELAYED FISSION FROM ~(230)Ac

摘要: 用 6 0MeV/u18O离子轰击ThO2 ,通过多核子转移和靶的耗散碎裂反应产生2 3 0 Ra。利用放射化学分离技术 ,将镭与钍及其它反应产物分离并制备成薄镭源。该源对云母裂变径迹探测器暴光 ,用高纯锗探测器测量镭源的γ活度 ;用氢氟酸溶液对云母箔进行蚀刻 ,使用光学显微镜观测云母箔中的裂变径迹。首次观测到了可能来自2 3 0 Acβ延发裂变的两个事件 ,获得它的 β延发裂变几率为 (1 19± 0 85 )× 10 -8。
- 230Ac /
- β延发裂变 /
- 化学分离 /
- 裂变几率
Abstract: ThO 2 is irradiated with 60 MeV/u 18 O beams. 230 Ra is produced via the multi nucleon transfer and dissipative fragmentation reactions of the target. 230 Ra is radio chemically separated from ThO 2 and the other reaction products. The thin Ra sources are prepared. The mica fission track detectors are exposed to the Ra sources. γ Rays of Ra decay in the sources are measured by a HPGe detector. The mica foil is etched in HF solution. The etched mica foil is scanned with an optical microscope. The fission tracks that should come from β delayed fission of 230 Ac are observed. The β delayed fission probability of 230 Ac is determined to be (1.19±0.85)×10 -8 .
- Ac /
- β delayed fission /
- chemical separation /
- fission probability

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