核事故剂量ESR测量方法的初步研究

PRELIMINARY STUDY OF ESR DOSIMETRY FOR NUCLEAR ACCIDENTS

用电子自旋共振(ESR)技术对0—50 Gy ^(60)Co γ射线照射前后的人骨、指甲、头发和手表材料、布料、塑料、香烟材料等十余种人身佩带物材料 ESR 信号的某些剂量学特性及其与照射剂量之间的关系进行了实验研究。结果表明,人骨和手表玻璃的信号强度对辐照剂量呈良好的线性关系,相关系数分别为:人骨,r=0.995;手表玻璃,r=0.999。在室温下,人骨的 ESR 信号很稳定,手表玻璃的信号经24 h 有约20%的衰减(24℃保存),降低保存温度可使信号衰减速度大为下降。两种材料的可测剂量下限均低于2 Gy。上述结果提示:人骨和手表玻璃可作为实用的核事故剂量 ESR 检测材料。实验中所选用的其它材料用于事故剂量的测量尚存在一些问题。

Electron spin resonance(ESR)technique was used to detect the ESR signal feature and therelations between signal intensity and irradiation dose of 0—50 Gy of ^(60)Co γ ray for human bone,fingernail,hair and more than ten kinds of people carriable materials such as materials from watch,clothes,plastic ballpen,cigarette and so on.The results showed that both bone and watch glass have agood linear relation between signal intensity and irradiation dose.The linear correlation factor γ is 0.995 for bone and γ is 0.999 for watch glass.At room temperature,signal from human bone hasexellent stability while watch glass has a decay of about 20% during 24 hours at 24℃.The decayingrate of watch glass will fall down at lower temperature.The lower limit of detectable dose for thesetwo materials is below 2 Gy.The results suggest that both human bone and watch glass can beapplicable as ESR dosimeter materials for nuclear accidents.Other materials investigated in this workstill have some problems to be solved for accidental dosimetric use.