Mn AMS at the University of Notre Dame's Nuclear Science Laboratory (NSL)*

⁵³Mn is a rare, radioactive isotope with a half-life of 3.74 million years which has astrophysical applications as an early solar system chronometer and as a test of nucleosynthesis models of supernovae and asymptotic giant branch (AGB) stars. In addition, ⁵³Mn has geological applications in determining ferromanganese minerals' surface exposure and burial age. To fully exploit the capabilities of ⁵³Mn as a chronometer, a sensitivity to the ⁵³Mn/⁵⁵Mn ratio of 1x10^-13 is necessary. Due to this low ratio, and interference from the naturally abundant ⁵³Cr isobar, Accelerator Mass Spectrometry (AMS) is the only technique sensitive enough to make these isotopic ratio measurements. However, the detection limit among active facilities remains on the order of 10^-13. At the University of Notre Dame’s Nuclear Science Laboratory (NSL), work is ongoing to develop ⁵³Mn AMS capability using a 10 MV FN tandem accelerator and a Browne–Buechner Spectrograph operated as a gas-filled magnet. During previous experiments, meteoric samples with ⁵³Mn/⁵⁵Mn ratios between 10^-10 and 10^-8 were measured. This presentation discusses the results of varying the experimental parameters on the detection limit.