Hamburg 2009 – scientific programme

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AGA: Arbeitsgruppe Physik und Abrüstung

AGA 5: Verification and Detection

AGA 5.2: Talk

Friday, March 6, 2009, 11:00–11:30, VMP 9 HS

Kr-85 signatures for various plutonium production schemes — •Paul Stanoszek — Carl Friedrich von Weizsäcker-Centre for Science and Peace research

Kr-85 is considered to be the best atmospheric indicator of unreported weapon-grade material production. This fact is based on the half-life of 10.76 years of Kr-85 and its chemical inactivity, which makes it even detectable after extended periods of cooling time. Kr-85 is produced as fission product during nuclear reactor operation and remains in the fuel until reprocessing starts. In order to determine the detectability of plutonium production the Kr-85 source term has to be assessed. The important issue of this presentation is the question on the minimum signal that an inspector can expect under the assumption that a proliferator minimizes his Kr-85 generation in order to circumvent a Kr-85 detection. A further assumption is that for nuclear weapon production a burn-up of typically around 2 MWd/kg is used. In addition, if clandestine plutonium production takes place, the source term might be used to estimate the amount of separated plutonium. The methodology of this study is based on a linkage between MCNPX and MATLAB. All results for actinide concentrations and Kr-85 are evaluated for different enrichments of U-235 and compared to known literature data. The Kr-85 source term per kilogram plutonium depends on the enrichments. As a result the lowest Kr-85 source term is found for depleted uranium.