National Electrostatics Corporation recently developed a single-stage AMS system (SSAMS) which lends itself to the exciting idea of being able to do AMS with positive ions. This is because ions are accelerated over a single electrostatic potential difference and no change of charge state from negative to positive in a stripper is required. But the stripper can still be used to suppress molecular interferences in a positive ion mass spectrum. By switching the polarity of the deck voltage and all other ion-optical elements on the low-energy side of the stripper, positive ions can potentially be analysed the same way as negative ions are. For obvious reasons positive ion production would have to be accomplished by means other than sputtering with caesium and a variety of positive ion sources already exist. SUERC is procuring a SSAMS with conventional gas-ready ion source, to which will be connected our existent gas sample handling system. The combination will provide extra capacity for compound specific radiocarbon AMS development. The instrument will also include the bipolar functionality necessary to analyse positive ions and a microwave ion source for proof-of-principle positive ion tests. This presentation will revolve around existing ideas for development work and applications of positive ion AMS on the new SUERC SSAMS.
See more of New Innovations and Revolutionary Concepts
See more of The 10th International Conference on Accelerator Mass Spectrometry (September 5-10, 2005)