Resonance ionization mass spectroscopy

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Laser Resonance Ionization Mass Spectrometry (RIMS) is a modern technique, which finds most of its practical applications in environmental, laser isotope separation or elemental ultra-trace analysis. RIMS excites the valence electron of an atom through several energy levels until it is stripped. The atom thus turns into a charged particle, which is easily be manipulated by electric fields. The power of the RIMS technique stems from the element selectivity of resonant laser excitation combined with the mass selectivity of modern separators. As a result a highly selective, yet highly sensitive instrument is at hand - exactly what is needed to investigate and selectively extract the minute quantities of short-lived, rare-isotopes produced at TRIUMF's Isotope Separator and Accelerator ISAC facility. At ISAC, higher ionization efficiency and higher selectivity transpire directly into shorter, yet more precise measurements of nuclear parameters. These nuclear quantities are the window into the world of subatomic physics. The RIMS program trains graduate students in high-resolution and precision laser spectroscopy techniques, along with nuclear physics expertise. Effective laser excitation schemes are to be developed for at least 10 elements that so far have not been accessible or required high powered, un-specific laser sources for ionization. This can be achieved by investigating the mostly uncharted auto-ionizing (AI) atomic states by resonance ionization spectroscopy. The AI greatly reduce the laser power required for ionization and add another unique excitation step ionization scheme. For many elements an order of magnitude improvement in ionization efficiency is expected. The first element to be investigated will be Astatine - the rarest of all elements on earth, yet, it is produced at ISAC. A successful development of laser excitation schemes will keep Canada's National Laboratory for Nuclear and Particle Physics: TRIUMF in the lead by providing the most intense and most exotic rare isotope beams available. This will attract the best groups world wide in nuclear and particle physics to continue to come to Vancouver in their quest for answers on the inner makings of matter.