Estimation of 134 Cs activity by a new approximation referred to the sum-peak method via a well-type Ge detector

Radiocesium monitoring in sediments and river water has been conducted along five rivers in Minami-Soma City during 2012–2016 to clarify the temporal changes of radiocesium contamination in these rivers. Sampling has been performed annually under normal flow conditions. Sediment and river water samples were collected from four or five sampling sites along each river. Gamma-ray measurements of sediments were performed using a low-background Ge detector and unfiltered river water was utilized to determine radiocesium concentration using a well-type Ge detector. The 137Cs concentration in sediments was highest at upstream sites and slowly decreased to downstream sites for all rivers reflecting the high radioactive contamination in the upstream area. Temporal decrease of the 137Cs concentration was observed in sediments and river water for each river. The effective half-lives were 1.3–2.1 y for sediments, and 0.9–2.1 y for river water from rivers with upstream dams. On the undammed river, the effective half-lives were 4.7 y and 3.7 y for sediment and river water, respectively. Much longer effective-half-lives might reflect the direct transfer of radiocesium from forests and plains to the river. The 137Cs concentration in riverbed was low in downstream areas, however, accumulation of 137Cs over the floodplain was observed. Rapid decrease of 137Cs contamination through rivers will put residents at ease, but high accumulation of radiocesium over floodplains should be noted for future river decontamination.

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Comparison of a coaxial Ge(Li) and a planar Ge detector in instrumental neutron activation analysis of geologic materials

Journal of Radioanalytical Chemistry ◽

10.1007/bf02517022 ◽

1977 ◽

Vol 36 (2) ◽

pp. 557-564 ◽

Cited By ~ 14

Author(s):

H. H. Schock

Keyword(s):

Neutron Activation Analysis ◽

Instrumental Neutron Activation Analysis ◽

Activation Analysis ◽

Neutron Activation ◽

Geologic Materials ◽

Ge Detector ◽

Instrumental Neutron Activation

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Unfolding of Ge-detector response by Monte Carlo simulation and applications in radiation protection

Progress in Nuclear Energy ◽

10.1016/0149-1970(90)90051-6 ◽

1990 ◽

Vol 24 (1-3) ◽

pp. 321-326 ◽

Cited By ~ 4

Author(s):

R. Meckbach ◽

P. Jacob

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Radiation Protection ◽

Detector Response ◽

Ge Detector

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In situ gamma spectrometry using portable HPGe detector. Radiological characterization and environmental surveillance around an operating nuclear power plant. Possibilities and limits

Journal of Radiological Protection ◽

10.1088/1361-6498/ac4116 ◽

2021 ◽

Author(s):

Jose Angel Corbacho ◽

A Baeza

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Gamma Spectrometry ◽

Nuclear Power ◽

Power Plants ◽

Activity Concentration ◽

Versatile Tool ◽

Ge Detector ◽

Radiological Characterization

Abstract In situ technique for measuring radionuclides in the soil using a portable Ge detector is a highly versatile tool for both the radiological characterization and for the monitoring of operating nuclear power plants. The main disadvantage of this technique is related to the lack of knowledge of the geometry of the source whose activity concentration is to be determined. However, its greatest advantage is the high spatial representability of the samples and the lower time and resource consumption than gamma spectrometry lab measurements. In this study, the possibilities and limits offered by in situ gamma spectrometry with a high resolution gamma portable detector in two common uses are shown: First, the radiological background characterization and its relationship with the geology of an area of 2700 km2 are assessed; Secondly, its potential for monitoring man-made activity concentration in soils located around an operating nuclear power plant in Spain for surveillance purposes is evaluated. Finally, high accuracy radiation maps have been prepared from the measurements carried out. These radiation maps are essential tools to know the radioactive background of an area, especially useful to assess artificial radioactive deposits produced after a nuclear accident or incident.

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