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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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Nuclear and Emerging Technologies for Space (NETS 2023)
May 7–11, 2023
Idaho Falls, ID|Snake River Event Center
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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February 2023
Latest News
Wanted: Information leading to a neutron source for fusion energy R&D
The Department of Energy’s Office of Science published a notice in the March 27 Federal Register calling for input on technological approaches to a Fusion Prototypic Neutron Source (FPNS) for materials irradiation research under DOE-SC’s Fusion Energy Sciences program, as well as partnership models that could accelerate the construction and delivery of the facility. The request for information (RFI) calls for responses by May 11.
Manoj K. Prasad, Neal J. Snyderman
Nuclear Science and Engineering | Volume 172 | Number 3 | November 2012 | Pages 300-326
Technical Paper | doi.org/10.13182/NSE11-86
Articles are hosted by Taylor and Francis Online.
The neutron counting probability distribution for a multiplying medium was shown by Hage and Cifarelli to be a generalized Poisson distribution that depends on the fission chain number distribution. An analytic formula is obtained for this number distribution, the probability to produce a number of neutrons in a fission chain. The formula depends on the probability that a fission spectrum neutron induces a subsequent fission and depends on the probability distribution for a specific number of neutrons to be produced in an individual induced fission. The formula is an exact solution to a functional equation due to Böhnel for the probability generating function. The Böhnel equation is derived as the t [right arrow] limit of a rate equation for a neutron population generating function, related to a rate equation studied by Feynman. The Böhnel equation is also shown to be a fixed point of an iteration problem, related to one studied by Hawkins and Ulam, where the iteration generates the chain a generation at a time. The discrete iteration problem is shown to be connected to the continuous time evolution of the chain. An explicit solution for the time evolution of the chain is given in the simplified approximation where at most two neutrons are created by an induced fission. The t [right arrow] limit of this equation gives a simple analytic expression for the solution to the Böhnel equation in this approximation. A generalized Poisson counting distribution constructed from the theoretical fission chain probability number distribution is compared to experimental data for a multiplying Pu sample.