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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
U.K.’s NWS gets input from young people on geological disposal
Nuclear Waste Services, the radioactive waste management subsidiary of the United Kingdom’s Nuclear Decommissioning Authority, has reported on its inaugural year of the National Youth Forum on Geological Disposal forum. NWS set up the initiative, in partnership with the environmental consultancy firm ARUP and the not-for-profit organization The Young Foundation, to give young people the chance to share their views on the government’s plans to develop a geological disposal facility (GDF) for the safe, secure, and long-term disposal of radioactive waste.
Jaakko Leppänen
Nuclear Technology | Volume 205 | Number 11 | November 2019 | Pages 1416-1432
Technical Paper | doi.org/10.1080/00295450.2019.1603710
Articles are hosted by Taylor and Francis Online.
A deterministic importance solver has been implemented as an internal subroutine in the Serpent 2 Monte Carlo code for the purpose of producing weight-window meshes for variance reduction. The routine solves the adjoint transport problem using the response matrix method with coupling coefficients obtained from a conventional forward Monte Carlo simulation. The methodology can be applied to photon and neutron external source problems, and the solver supports multiple energy groups and several mesh types. Importances can be generated with respect to multiple responses, and an iterative global variance reduction sequence enables distributing the transported particle population evenly throughout the geometry. This paper describes the methodology applied in the response matrix solver and presents a verification for the generated importance functions through simple demonstrations. A practical example involving a photon shielding problem is included for performance evaluation.