Haskell E H, Hayes R B, Kenner G H
Center for Applied Dosimetry, Division of Radiobiology, University of Utah, Salt Lake City 84112, USA.
Health Phys. 1999 Feb;76(2):137-44. doi: 10.1097/00004032-199902000-00005.
Electron paramagnetic resonance dosimetry may be applied to whole deciduous teeth of children. This makes it feasible to make direct measurement of absorbed gamma ray dose in the days and weeks following a nuclear accident, particularly if used in conjunction with a public awareness program. The technique reported here requires little sample preparation and has resulted in precision of approximately 30 mGy (1 sigma) for a deciduous incisor. Under conditions for rapid screening procedures, the methodology is estimated to provide 0.5 Gy accuracy. The largest error in the process is the determination of an appropriate background native signal for subtraction from the whole tooth spectrum. The native signal is superimposed on the radiation-induced signal, and the subtraction requires knowledge of a sample's relative content of enamel and dentin along with their relative native signal intensities. Using a composite background standard, an equivalent absorbed dose of 70+/-38 mGy (1 sigma) was determined. The lower detection limit of the technique was achieved by the elimination of anisotropic effects through rotation of the sample during measurement, together with subtraction of the standard native background signal and empty tube background spectra from the sample spectra.
电子顺磁共振剂量测定法可应用于儿童的整个乳牙。这使得在核事故后的数天和数周内直接测量吸收的伽马射线剂量成为可能，特别是如果与公众意识计划结合使用的话。本文报道的技术所需的样品制备很少，对于一颗乳切牙，测量精度约为30毫戈瑞（1σ）。在快速筛查程序的条件下，该方法估计可提供0.5戈瑞的准确度。该过程中最大的误差在于确定从整个牙齿光谱中减去的合适的本底天然信号。天然信号叠加在辐射诱导信号上，减法需要了解样品中牙釉质和牙本质的相对含量及其相对天然信号强度。使用复合本底标准，确定了70±38毫戈瑞（1σ）的等效吸收剂量。该技术的较低检测限是通过在测量过程中旋转样品消除各向异性效应，以及从样品光谱中减去标准天然本底信号和空管本底光谱来实现的。
