【摘要】 建立了基于效率计算的液闪三双符合比活度测量装置,通过设定甄别阈、扩展死时间、符合技术手段消除了光电倍增管的热噪声和余后脉冲的影响。该装置测量氚水、¹⁴C和⁹⁹Tc的双管符合探测效率达到54%、96.2%和97.2%。用NIST氚水标准物质对新建立的实验装置进行验证,E_n数检验结果满意。更多还原

【Abstract】 The liquid scintillation triple-to-double coincidence ratio（TDCR） system recently constructed is presented.In order to eliminate the influence of after pluses and thermal noises,the technology of discrimination threshold setting,coincidence counting and extendible dead time is in application.The highest efficiency of tritium water,¹⁴C and ⁹⁹Tc is about 54%,96.2% and 97.2%separately.The NIST SRM of tritium water is measured to verify the performance of the counter,and the result agreed well with certified activitiy value with E_n criterion.更多还原