Estimation of the Two-Dimensional Power Spectral Density of Spatial Fluctuation in Terrestrial Gamma-Ray Dose Rate

• MINATO Susumu

  National Industrial Research Institute of Nagoya

Bibliographic Information

Other Title

• 地表γ線線量率分布の揺らぎに関する二次元パワースペクトルの推定

Abstract

The multiple regression analysis done for 50 sets of data of natural terrestrial gamma-ray dose rates collected from different sites of the world led to an empirical formula for the variance of the data as a function of mean value and area. The mean values and areas studied in this paper range from 10 to 100 (nGy/h) and from 10^-3 to 10⁷ (km²), respectively. For an isotropic field of fluctuation, a two-dimensional power spectral density (2D PSD) was derived theoretically from the above mentioned empirical formula in a form of S (k) =0.952×10^-3m^2.02k^-2.36, where k (cycles/km) and m (nGy/h) are the wave number and the mean, respectively. The validity of the estimated 2D PSD was confirmed by comparing with PSDs obtained by the following two methods. One is the spatial auto-correlation analysis for several sets of randomly distributed 2D data consisting of more than 170 samples taken through ground surveys. The other is the direct 2D Fourier transform for two sets of 100×100 data matrix picked up from a dose rate map produced through airborne surveys.

Journal

• RADIOISOTOPES

  RADIOISOTOPES 49 (8), 398-408, 2000

  Japan Radioisotope Association

Keywords

• terrestrial gamma-ray
• dose rate
• spatial fluctuation
• 2D power spectral density

Details

• CRID: 1390001204154835968
• NII Article ID: 10004588246
• NII Book ID: AN00351589
• DOI: 10.3769/radioisotopes.49.398
• ISSN: 18844111
• ISSN: 00338303
• NDL BIB ID: 5438526
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I5438526
• Web Site: https://www.jstage.jst.go.jp/article/radioisotopes1952/49/8/49_8_398/_pdf
• Data Source:
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  • CiNii Articles
• Abstract License Flag: Disallowed