【摘要】 用9个“单能”的标准水溶液源,刻度得到有自吸收后的峰效率、总效率。对放置于相对效率100%的HPGe探测器上表面的土壤体源的60Co、152Eu和154Eu真符合相加进行了研究。用校正自吸收后的效率曲线和60Co、152Eu、154Eu标准源测量结果比较,得到60Co1173和1332keV校正因子实验值分别为1.10和1.14。根据衰变纲图和效率,计算了这3个核素几个典型峰的校正因子,其中60Co的1173和1332keV因子分别为1.10和1.11。在探测器表面和远距离测量同一强样品,用样品中没有级联相加的核素137Cs作过渡核素,得到的样品中各核素真符合校正因子与其它方法得到的因子符合得较好。更多还原

【Abstract】 Nine “single energy” gamma standard solutions are used to calibrate the peak and total efficiencies. True coincidence summing(TCS) corrections in γ spectrum analysis of 60Co、152Eu and 154Eu in cylindrical volume soil samples measured on the top of a HPGe detector with 100% relative efficiency have been studied. The experimental TCS correction factors have been measured by comparing the calibrated efficiency function after correction for self absorption and the efficiencies measured by using standard soil sources, which are 1.10 and 1.14, respectively, for 60Co 1173 and 1332 keV γ-rays. TCS correction factors have also been calculated by using efficiency functions and decay schemes,which are 1.10 and 1.11, respectively, for 60Co 1173 and 1332 keV γ-rays. A relatively strong sample has been chosen to be measured on and far away from the detector surface, and the 137Cs 661 keV peak has been used as a transition to get the TCS correction factors, which agree satisfactorily with those derived by other methods.更多还原