The half-life for 79Se decay is calculated by using the Logf1ut systematics method. Based on the data analysis and comparison with experimental data the 79Se half-life is recommended. The scheme for 79Se decay is also...The half-life for 79Se decay is calculated by using the Logf1ut systematics method. Based on the data analysis and comparison with experimental data the 79Se half-life is recommended. The scheme for 79Se decay is also shown and the radiation data are calculated in the text.展开更多
The accelerator mass spectrometry（AMS） is an effective method for the determination of the half-life of long-lived radionuclides. In this paper, we report a method for measurement of the half-life of ^79Se. The numb...The accelerator mass spectrometry（AMS） is an effective method for the determination of the half-life of long-lived radionuclides. In this paper, we report a method for measurement of the half-life of ^79Se. The number of ^79Se atoms was determined from measured ^79Se/Se absolute ratios with the AMS system at the China Institute of Atomic Energy and the decay rate of ^79Se was determined by counting the emitted β-rays with a liquid scintillation spectrometer. The major improvements of our measurements include using the high abundance of an ^79Se sample which was cooled for many years to exclude the interference of short-lived nuclides, the extraction of SeO-2molecular ions, that results in a suppression of the ^79Br background by as much as about five orders of magnitude. Also, an AMS measurement of the absolute ratio of ^79Se/Se was developed to avoid systematic errors. The results show that ^79Se/Se is（2.35±0.12）×10^-7in the reference sample and the radioactivity of ^79Se is（1.24±0.05） Bq/g, so the half-life of ^79Se is（2.78±0.18）×10^5a.展开更多
文摘The half-life for 79Se decay is calculated by using the Logf1ut systematics method. Based on the data analysis and comparison with experimental data the 79Se half-life is recommended. The scheme for 79Se decay is also shown and the radiation data are calculated in the text.
基金Supported by National Natural Science Foundation of China(11175266)
文摘The accelerator mass spectrometry（AMS） is an effective method for the determination of the half-life of long-lived radionuclides. In this paper, we report a method for measurement of the half-life of ^79Se. The number of ^79Se atoms was determined from measured ^79Se/Se absolute ratios with the AMS system at the China Institute of Atomic Energy and the decay rate of ^79Se was determined by counting the emitted β-rays with a liquid scintillation spectrometer. The major improvements of our measurements include using the high abundance of an ^79Se sample which was cooled for many years to exclude the interference of short-lived nuclides, the extraction of SeO-2molecular ions, that results in a suppression of the ^79Br background by as much as about five orders of magnitude. Also, an AMS measurement of the absolute ratio of ^79Se/Se was developed to avoid systematic errors. The results show that ^79Se/Se is（2.35±0.12）×10^-7in the reference sample and the radioactivity of ^79Se is（1.24±0.05） Bq/g, so the half-life of ^79Se is（2.78±0.18）×10^5a.
