GM计数管是一种应用广泛的核辐射探测器,但量程范围较窄,扩展其量程能进一步拓宽其应用范围。回顾了国内外扩展GM计数管量程所采取的主要方法和措施,分析了采用死时间模型和函数拟合修正方法扩展量程存在的不足;简要介绍和分析了改变计数管工件方式或改进外部电路的量程扩展方法,重点介绍了近年来出现的time—to—count方法的工作原理。指出通过革新使用方式,改进计数管结构设计和筛选恰当材料,研制复合型探测器等途径,可大幅提高计数管的性能。
GM tube is a kind of widely used nuclear radiation detectors, whose range is rather narrow. Exten- ding range helps to enlarge GM tube' s application occasion. Domestic and overseas methods to extend GM tube' s range are reviewed. Major drawbacks are analyzed with methods of adopting dead time models and func- tion fitting. Methods of improving external circuits or changing operation mode of GM tube are briefly introduced and analyzed. Operation principle of time - to - count method is described in detail. It is suggested that GM tube performance could be boosted markedly by means of innovating operation mode, improving tube structure, siftin~ appropriate materials, developing composite detectors, and etc.