原子能科学技术2018，Vol.52Issue(4)：577-582,6.DOI:10.7538/yzk.2017.youxian.0556
240Am半衰期的测量
Measurement of Half-life of 240 Am
夏子恒 1师全林 1解峰 1凡金龙 1李雪松 1余功硕1
作者信息
- 1. 西北核技术研究所,陕西 西安 710024
- 折叠
摘要
Abstract
The half-life of 240 Am is of importance to determine the cross section of neutron reaction 241 Am(n, 2n)240 Am and the currently evaluated datum is 50. 8(3)h, which is an experimental result by monitoring the intensity of 987. 8keVγ-ray with a Ge(Li) detector over a period of 6d, less than 3times of the half-life of 240 Am. In this work, the detection efficiency of the high energyγ-rays for 240 Am increases greatly by using a well-type HPGe detector and an absorber made of Pb to attenuate the X-rays and low energyγ-rays. According to the simulation result from Geant4, the detection efficiency of the 888. 8keV and 987. 8keVγ-rays for 240 Am are 14. 1％ and 13. 3％ when the thickness of Pb absorber is 1 mm. Recently, about 500μg 242Pu was irradiated by protons on HI-13tandem accelerator in China Institute of Atomic Energy to produce240 Am by the reaction of 242Pu(p, 3n)240 Am. The solution source containing 240 Am about 700Bq was measured with the well-type HPGe detector. The intensities of 888. 8keV and 987. 8keVγ-rays for 240 Am were measured continuously more than 18dand the half-life of 240 Am is calculated to be 50. 79(5)h by least square method, which is consistent with the evaluated datum.关键词
240 Am/半衰期/阱型HPGe探测器Key words
240 Am/half-life/well-type HPGe detector分类
数理科学引用本文复制引用
夏子恒,师全林,解峰,凡金龙,李雪松,余功硕..240Am半衰期的测量[J].原子能科学技术,2018,52(4):577-582,6.
