<速報>鈴鹿市における大地からの自然放射線量および放射能地図の作成

概要

論文の詳細を見る
Man lives in the environment of naturally occurring radiation and radioactivities. The need for accurate, reliable and interpretable measurements of environmental radiation and radioactivity has increased steadily. Such requirements as the assessment of exposure to man from natural sources are part of this need. Interpretation of measurements is aided by a prior knowledge of the characteristics of typical radiation fields and radionuclide distributions. Environmental radionuclides can be divided mainly into three groups according to origin : (1) those of primordial origin (that is, of sufficiently long half-life to have survived in detectable quantities since the formation of the earth), together with their radioactive daughters; (2) those successively produced by natural processes other than decay of primordial radionuclides; and (3) those generated by man's activities. This paper focused on the radiation exposure to man from primordial radionuclides distributed in soil, and making maps due to radiation exposure and radioactive nuclides distributed in soil in Suzuka city. A map of Suzuka city was divided into 3 km×3 km meshes. A point for measurements was set inside the mesh and the point was selected as having natural surfaces as possible. Measurements were made with a 3"Φ×3"l Nal (Tl) scintillation spectrometer. A pulse-height distribution observed was unfolded into an incident γ-ray spectrum with 22×22 response matrix of the measuring system applying an iteration method. Radiation exposure to man and concentrations of the naturally occurring radioniclides in the soil were obtained from the incident γ-ray spectrum assuming their homogeneous distribution in the soil. Radiation exposure was higher in the areas in the west of the city, and became gradually lower to the east. Mountainous areas are located in the west part of the city. They are geologically composed of granite rocks. Naturally occurring radionuclides are abundantly contained in the rocks. Those nuclides are released into soil by natural weathering processes. The maps reflected the distribution of the nuclides in soil. An averaged annually effective dose equivalent was estimated as 0.57 mSv.
鈴鹿医療科学大学の論文
1998-03-30

<速報>鈴鹿市における大地からの自然放射線量および放射能地図の作成

スポンサーリンク

概要

著者

関連論文

スポンサーリンク