Monitoring uranium enrichment remains an important problem for nonproliferation andsafeguards. Current technologies which measure the ~(235)U enrichment in UF_6 cylinders requirecontrolled conditions for accurate measurements, and utilize gamma and low energy neutronsignatures which measure only the outside surface of large, dense UF_6 volumes. This results in anon-robust measurement which could be exploited through diversion. Fast neutron spectrometryand imaging can be applied to fill this gap, as the high energy neutrons are deeply penetratingand carry the potential to allow for whole cylinder measurements. While this measurementconcept has been explored before in simulation, here we will discuss a practical deployment ofthe technique. A suite of detectors were deployed to the Paducah Gaseous Diffusion Plant inJuly of 2012, including several different liquid scintillator cells (EJ-309), a ~3He tube, and a largesodium iodide scintillator. We will focus on the fast neutron response of the liquid scintillator,our efforts to characterize multiple UF_6 30B cylinders of varying enrichment using spectral andrate information, and our attempts to compare our results to previous simulations. Initial effortsdemonstrate the ability to correlate the shape of the neutron energy spectrum data to theenrichment of the 30B cylinder.
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