11:00 AM - 12:00 PM
Anton Wallner, National University, Canberra, Australia
Physics Division Seminar
Building 6008, Large Conference Room
Email: Alfredo Galindo-UribarriPhone:
Accelerator mass spectrometry (AMS) represents a direct atom-counting technique with unsurpassed sensitivity for studying long-lived radionuclides. In this talk, I will highlight some AMS applications involving actinides:
(i) The search for live supernova-produced radionuclides in terrestrial archives. Such studies probe directly specific nucleosynthesis sites and will help understanding heavy element nucleosynthesis in massive stars. Interstellar Pu-244 (t1/2 = 81 Myr) is a perfect nuclide to study r-process nucleosynthesis that serves also as a probe for r-process sites.
(ii) Improved and highly accurate nuclear data are urgently required for the design of advanced reactor concepts. Neutron activation with subsequent AMS measurement of the reaction products represents a new independent and complementary method. Such data serve as important anchor points to solve present discrepancies as well as impact on data used in the nuclear astrophysics community.
(iii) The concentrations of actinides in our environment provide unique information and can give valuable information on its sources. Their isotopic fingerprint allows tracing anthropogenic activities (e.g., from nuclear weapons tests, accidental local fallout products, nuclear-fuel reprocessing plants) or environmental processes (soil erosion, climate change).
Refreshments served at 2:40.