Apparatus development for measurement of (134)Cs and (137)Cs radioactivity of soil contaminated by the Fukushima Daiichi Nuclear Power Plant accident

Appl Radiat Isot. 2016 Sep:115:4-7. doi: 10.1016/j.apradiso.2016.06.003. Epub 2016 Jun 4.

Abstract

We developed an apparatus containing a NaI(Tl) scintillator to measure the (134)Cs and (137)Cs radioactivity of soil contaminated by the Fukushima Daiichi Nuclear Power Plant accident. The unfolding method with the least-squares technique was used to determine the radioactivity. Detector responses for each radionuclide in soil were calculated with EGS5 code for the unfolding method. The radionuclides that were measured were (40)K, (134)Cs, (137)Cs, (208)Tl, (214)Bi, and (228)Ac. The measured spectrum agreed well with the spectrum calculated from the response matrix and measured radioactivities. The unfolding method allows us to use the NaI(Tl) scintillator despite the overlap of peaks.

Keywords: (134)Cs; (137)Cs; Fukushima Daiichi Nuclear Power Plant; Soil radioactivity; Unfolding method.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cesium Radioisotopes / analysis*
  • Equipment Design
  • Fukushima Nuclear Accident*
  • Gamma Rays
  • Least-Squares Analysis
  • Scintillation Counting / instrumentation*
  • Scintillation Counting / statistics & numerical data
  • Soil Pollutants, Radioactive / analysis*

Substances

  • Cesium Radioisotopes
  • Soil Pollutants, Radioactive