Concerning the time dependence of the decay rate of 137Cs.
نویسندگان
چکیده
The decay rates of eight nuclides ((85)Kr, (90)Sr, (108)Ag, (133)Ba, (137)Cs, (152)Eu, (154)Eu, and (226)Ra) were monitored by the standards group at the Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany, over the time frame June 1999 to November 2008. We find that the PTB measurements of the decay rate of (137)Cs show no evidence of an annual oscillation, in agreement with the recent report by Bellotti et al. However, power spectrum analysis of PTB measurements of a (133)Ba standard, measured in the same detector system, does show such evidence. This result is consistent with our finding that different nuclides have different sensitivities to whatever external influences are responsible for the observed periodic variations.
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عنوان ژورنال:
- Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
دوره 74 شماره
صفحات -
تاریخ انتشار 2013