Actinides are elements with atomic masses heavier than Thorium. The application of actinide measurements spans many fields. A few common examples include:

• Nuclear forensic studies to identify the source of nuclear material
• Environmental monitoring programs to ensure that discharges from nuclear facilities comply with regulations
• Health physics studies to estimate human exposure to radioactivity
• Uranium exploration to find new ore deposits
• Waste management studies to ensure that radioactive wastes are not migrating from safe stored facilities



The AE Lalonde AMS system was designed to measure heavy isotopes up to 380 atomic mass units including the actinide elements such as U, Pu, and Am. The AEL accelerator system has several unique features that permit this kind of analysis:

(1) a high resolution magnet in the low energy beam line to maximize the selection of heavy isotopes of interest
(2) a very large magnet in the high energy section of the beam line to bend beams of heavy ions
(3) an innovation line that can be used to test separations of isobaric actinides such as U238 and Pu238 using an Isobar Separator for Anions (ISA)

The AE Lalonde AMS laboratory is supported by two actinide radiochemical laboratories – one for low level or environmental analyses and the second for samples such as uranium ore that contain higher levels of radionuclides. Radiometric counting equipment for alpha beta and gamma measurements is also available to supplement AMS analyses.

Other mass spectrometry facilities located within the ARC include SIMS, ICP-MS, Laser Ablation ICP-MS, and ICP-OES. These techniques enable problems to be addressed using multivariate and multi-technique approaches. AEL staff have extensive experience measuring actinide elements and they have pioneered new techniques for measuring isotopes of thorium, uranium, plutonium, americium and curium.


If you have a question about measuring actinides contact: Dr Xiaolei Zhao ( or Barbara Francisco (