A high output, large acceptance injector for the NOSAMS Tandetron AMS system

We have completed a major upgrade of the National Ocean Sciences AMS Facility (NOSAMS) Tandetron AMS system in two stages. First, the simultaneous (recombinator) injector was replaced with a fast-cycling sequential injector and changes to the low-energy acceleration section. Data after the injector commissioning show an improvement in background, with mean machine background (commercial graphite) of Fm 0.0004 (62 ka). Second, we replaced the original ion source with a high-output 40 sample MCSNICS source. This improved beam currents and raw ratio fractionation, and increased sample to detection efficiency fivefold.