4πβ+4πγ计数相加法绝对测量^(182)Ta溶液的放射性比活度

Absolute measurement of activity of ^(182)Ta using the 4πβ+4πγ counting meathod

182Ta发射低能和高能两组γ射线,半衰期适中,是HPGe探测器效率刻度的合适标准源之一。用4πβ+4πγ计数相加法绝对测量了182Ta溶液的放射性比活度1。82Ta通过反应堆活化得到,4πβ+4πγ计数相加装置对182Ta的总探测效率高达99%以上,182Ta溶液比活度测量的相对合成标准不确定度为0.2%。

182Ta emits two groups γ-rays in the low and high energy range.And it has a moderate long half-life,so that it is one of the suitable standard sources to calibrate the efficiency curve of HPGe detectors.The specific activity of 182Ta solutionwas measured using the 4πβ+4πγ counting meathod.Sources of 182Ta were produced by thermal neutron in the reactor.The total efficiency of 4πβ+4πγ counting deviceto 182Ta reaches above 99%,and the relativetly combined standard uncertainty of the specific activity is 0.2%.