Production and release rate of 37Ar from the UT TRIGA Mark-II research reactor

Abstract Air samples were taken at various locations around The University of Texas at Austin's TRIGA Mark II research reactor and analyzed to determine the concentrations of 37 Ar, 41 Ar, and 133 Xe present. The measured ratio of 37 Ar/ 41 Ar and historical records of 41 Ar releases were then utilized to estimate an annual average release rate of 37 Ar from the reactor facility. Using the calculated release rate, atmospheric transport modeling was performed in order to determine the potential impact of research reactor operations on nearby treaty verification activities. Results suggest that small research reactors (∼1 MWt) do not release 37 Ar in concentrations measurable by currently proposed OSI detection equipment.