Applications of Accelerator Mass Spectrometry in Nuclear Verification

The reduction and eventual elimination of nuclear threats toglobal peace and security remains a high priority for governmentsaround the world.1 The approach towards this goal involvesmultiple paths, including through existing treaties, such as theNon-proliferation Treaty (NPT), through bringing into forcetreaties and agreements such as the Additional Protocol and theComprehensive Test Ban Treaty, and through the negotiation andenactment of new arms reduction measures and treaties such asthe Fissile Material Cut-off Treaty. In all cases, trust between theparties to these agreements is built on sets of arrangements forverification.Verification entails credible quantification and gathering ofsound evidence, using scientifically proven methods. Not onlymust the best available methods be brought to bear, but also newmethods must be researched, proven and implemented. Thusagencies responsible for nuclear verification provide drivers fordevelopment and innovation in the sciences and technologiesapplicable to verification. This does not necessarily involve thedevelopment of novel technologies from scratch, but ratherthrough interaction with those parts of the scientific communitywho already utilise methods which can be adapted for verificationpurposes.One such example is Accelerator Mass Spectrometry(AMS).2,3 AMS was originally demonstrated in the late 1970sas a means for detection of radiocarbon at natural abundancelevels. The technique quickly expanded to a number of otherlong-lived radioisotopes, and now stands as the most sensitivemethod available for the detection of long-lived radioisotopes atultra-trace levels. In the next section we will introduce the AMStechnique, and then review its application to verification science.