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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA furloughs 1,400 employees, pays contractors until end of month
After nearly three weeks of a government shutdown, the Department of Energy’s National Nuclear Security Administration has furloughed 1,400 employees and has retained 400 as essential employees who will continue working without pay.
Scott D. Ramsey, Gregory J. Hutchens
Nuclear Science and Engineering | Volume 170 | Number 1 | January 2012 | Pages 1-15
Technical Paper | doi.org/10.13182/NSE10-26
Articles are hosted by Taylor and Francis Online.
While stochastic neutron transport theories have been developed in rigorous detail, many applications have historically been investigated using the point-kinetics formulation. In this work we develop a space-dependent model using the diffusion approximation to the Pál-Bell probability generating function equation, resulting in a nonlinear analog of the conventional time-dependent neutron diffusion equation. We investigate a variety of approximate solutions for the time- and space-dependent survival probability in one-dimensional symmetric, one-speed, isotropic, delayed neutron precursor-free systems, and compare them to counterpart point-kinetics results. Following the theoretical developments, we apply the new results in the context of a criticality accident scenario, from which the importance of spatial effects is revealed.