| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus that enables accurate online monitoring of cesium 134 (Cs-134) and cesium 137 (Cs-137), as well as strontium 90 (Sr-90) and yttrium 90 (Y-90), which are nuclides that emit only beta rays, in sea water, river water, or well water.SOLUTION: A radiation monitor comprises at least one gamma-ray detector 2 and at least one beta-ray detector 1. Concentration measurement data of nuclides that emit both gamma rays and beta rays is derived from energy spectrum data from the gamma-ray detector. Contribution of beta rays from the nuclides that emit both gamma rays and beta rays in the beta detector is derived from the concentration measurement data. The contribution of the beta rays from the nuclides that emit both gamma rays and beta rays in the beta detector is subtracted from a beta-ray count measured by the beta-ray detector to derive concentration of nuclides that emit only beta rays.SELECTED DRAWING: Figure 1 |
