The Evaluation of the 0.07 mm and 3 mm dose equivalent with a portable beta spectrometer

可搬型ベータ線スペクトロメータを用いた7m及び3mm線量当量の評価

星 勝也 ; 吉田 忠義 ; 辻村 憲雄   ; 岡田 和彦

Hoshi, Katsuya; Yoshida, Tadayoshi; Tsujimura, Norio; Okada, Kazuhiko

市販のスペクトロメータを使用して、いくつかのベータ核種についてスペクトルを測定した。得られたスペクトルの形状は理論値とよく一致した。パルス波高分布にエネルギーごとのICRP74の換算係数を乗じて、任意の深さの線量当量を評価した。スペクトルから評価した線量当量は線量率基準とよく一致した。

Beta spectra of various nuclide species were measured by commercially available compact spectrometer. The shape of spectra obtained from the spectrometer approximately agreed with that of theoretical spectra. The beta dose equivalent at any depths has been able to be obtained as a product of measured pulse height spectra and appropriate conversion coefficients of ICRP Publ. 74. The dose rates evaluated from the spectra were comparable to the reference dose rates of standard beta calibration sources. And, we were able to determine the dose equivalent with relative error of indication of 10% without the complicated correction.