Stabilized power supplies for thermal ionization MS

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Mass dependent processes and nuclear decays alter the relative abundances of the seven stable isotopes of the chemical element molybdenum.  High precision measurements of isotope abundance variations provide unique clues to the types and extents of these processes that occurred in terrestrial and extra-terrestrial environments. This information is critical to understand the fundamental nuclear processes that produce the heavy elements.  For example, our recent data from iron meteorites indicate that our Solar System was formed from the products of diverse nucleosynthetic sources.  In addition, high precision molybdenum isotope abundance data of samples of molybdenite ores collected from around the world show that small but relatively significant isotope abundance variations are correlated with the geological source of the molybdenum in the ore body and the temperature of formation of the mineral. The isotopic composition of molybdenum is measured by specialized mass spectrometric techniques.  Wieser operates a thermal ionization mass spectrometer that was originally designed and built by the National Institute of Standards and Technology in MD, USA.  This 30 year-old instrument was brought to Calgary in 2000 and made operational with support from the University of Calgary and NSERC.  Over the past five years, it has been used extensively for research in molybdenum isotope abundance variations in terrestrial and extra-terrestrial materials as part of international collaborative research projects.  The mass spectrometer is also a major tool for the training of students and technicians.  Our research goals now demand the highest levels of sensitivity and precision.  Therefore, strategic electronic upgrades to the thermal ionization mass spectrometer are necessary for us to make progress in our research efforts.  Several rare meteorite and billion year-old mineral samples cannot be analyzed until stable instrumental operating conditions are achieved.  The outcomes of our work will generate new knowledge of planetary physical, nuclear, and possibly biological processes in terrestrial and extra-terrestrial environments.