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arXiv · 1311.6620

Monte Carlo modeling of spallation targets containing uranium and americium

Yury Malyshkin·Igor Pshenichnov·Igor Mishustin·Walter Greiner
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Abstract

Neutron production and transport in spallation targets made of uranium and americium are studied with a Geant4-based code MCADS (Monte Carlo model for Accelerator Driven Systems). A good agreement of MCADS results with experimental data on neutron- and proton-induced reactions on $^{241}$Am and $^{243}$Am nuclei allows to use this model for simulations with extended Am targets. It was demonstrated that MCADS model can be used for calculating the values of critical mass for $^{233,235}$U, $^{237}$Np, $^{239}$Pu and $^{241}$Am. Several geometry options and material compositions (U, U+Am, Am, Am$_2$O$_3$) are considered for spallation targets to be used in Accelerator Driven Systems. All considered options operate as deep subcritical targets having neutron multiplication factor of $k \sim 0.5$. It is found that more than 4 kg of Am can be burned in one spallation target during the first year of operation.

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Yury Malyshkin, Igor Pshenichnov, Igor Mishustin, Walter Greiner. 2013-11-26. Monte Carlo modeling of spallation targets containing uranium and americium. https://doi.org/10.1016/j.nimb.2014.04.027

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