Keegan R P, Gehrke R J
Idaho National Engineering and Environmental Laboratory, Mail Stop 2114, P.O. Box 1625, Idaho Falls, Idaho 83415-2114, USA.
Appl Radiat Isot. 2003 Aug-Sep;59(2-3):137-43. doi: 10.1016/s0969-8043(03)00149-0.
A non-destructive technique to determine the time since last purification of weapons grade plutonium based on the 241Pu decay series has been developed and demonstrated to provide results that are consistent with our historical and process knowledge. This method is based on the use of the Bateman equations and the decay chain 241Pu-->237U & 241Am-->237Np-->233Pa. Secular equilibrium is assumed between the (2.1 x 10(6) year) 237Np and the (27 day) 233Pa. The proposed method is dependent upon the efficiency of the plutonium separation process but makes no assumption about the relative abundance of 241Pu in 239Pu. Even though the technique was developed for weapons grade plutonium, it is expected to apply to almost any material that contains plutonium.
一种基于钚-241衰变系列来确定武器级钚上次纯化时间的无损技术已被开发出来，并证明所提供的结果与我们的历史和工艺知识相符。该方法基于贝特曼方程以及241Pu→237U和241Am→237Np→233Pa的衰变链。假定半衰期为（2.1×10⁶年）的237Np与半衰期为（27天）的233Pa之间达到长期平衡。所提出的方法取决于钚分离过程的效率，但并不对239Pu中241Pu的相对丰度做任何假设。尽管该技术是针对武器级钚开发的，但预计几乎可应用于任何含钚材料。
