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November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
P. Chiovaro, P. A. Di Maio, S. Garitta, E. Vallone, G. Vella
Nuclear Science and Engineering | Volume 183 | Number 1 | May 2016 | Pages 52-64
Technical Paper | doi.org/10.13182/NSE15-68
Articles are hosted by Taylor and Francis Online.
This paper deals with the evaluation of the first flight escape probability of nuclear particles from convex bodies with spherical symmetry by means of some geometrical arguments and very simple probability considerations. The cases of a full sphere, a one-region spherical shell with an empty central zone, a spherical shell region containing a black central zone, and a full sphere with a sourceless shell have been considered. In all the aforementioned cases, a homogeneous medium and uniform isotropic source have been taken into account. Moreover, a simple and general formula has been derived for the calculation of the uncollided flux that is presupposed to be valid for arbitrary geometries. The results obtained have been validated by Monte Carlo analyses performed by the Monte Carlo N-Particle (MCNP5) code and critically discussed.