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May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Deep Fission to break ground this week
With about seven months left in the race to bring DOE-authorized test reactors on line by July 4, 2026, via the Reactor Pilot Program, Deep Fission has announced that it will break ground on its associated project on December 9 in Parsons, Kansas. It’s one of many companies in the program that has made significant headway in recent months.
Keisuke Kobayashi, Kenji Nishihara
Nuclear Science and Engineering | Volume 136 | Number 2 | October 2000 | Pages 272-281
Technical Paper | doi.org/10.13182/NSE00-A2158
Articles are hosted by Taylor and Francis Online.
Using an importance function describing the capability of a system for producing fission neutrons, a new definition of the subcriticality is proposed, which has the physical meaning of a multiplication factor in a real subcritical system with external sources. This multiplication factor ks, which expresses the number of fission neutrons produced by a fission neutron in a steady state, is different from the usual criticality factor or the effective multiplication factor keff, since the former is calculated from the inhomogeneous equation with external source, whereas the latter is calculated from the homogeneous criticality equation without external source.
