The Vienna Environmental Research Accelerator (VERA): A facility for Accelerator Mass Spectrometry of ALL isotopes
7 December 2016
NSCL Lecture Hall 1200
University of Vienna
Counting atoms rather than decays has revolutionized the use of long-lived radioisotopes with half-lives between 100 to 100 million years in many domains of our environment at large. Accelerator Mass Spectrometry (AMS) made it possible to measure radioisotope-to-stable isotope ratios down to 1e-16, with samples many orders of magnitude smaller than required for decay counting. The prime example is 14C, but many other radioisotopes (e.g. 10Be, 26Al, 36Cl, 41Ca, 129I, actinides) are also being measured with AMS. Because in some cases negative ions suppress very effectively background from stable isobars (e.g. negative ions of 14N are unstable), almost all AMS facility are based on tandem accelerators.
In the current talk, the Vienna Environmental Research Accelerator (VERA) AMS facility will be described, which is based on a 3-MV Pelletron tandem accelerator and is in operation at the University of Vienna since 20 years. VERA aims towards measuring ALL long-lived radioisotopes, irrespective of their mass. Recent efforts to arrive at this goal will be discussed, and the versatility of AMS experiments at VERA will be illustrated on a variety of applications ranging from archaeology to astrophysics.