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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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Latest News
Wyoming OKs construction of TerraPower’s Natrium plant
Progress continues for TerraPower’s Natrium plant, with the latest win coming in the form of a state permit for construction of nonnuclear portions of the advanced reactor.
F. Carloni, M. Marseguerra
Nuclear Science and Engineering | Volume 71 | Number 3 | September 1979 | Pages 319-326
Technical Paper | doi.org/10.13182/NSE79-A19069
Articles are hosted by Taylor and Francis Online.
The problem of determining the neutron and count distributions in a multiplying assembly has been independently solved by many authors over the past 30 years. In all cases, the quadratic approximation is used for the probability generating function of the neutrons emitted per fission. In the present paper, this approximation is interpreted as one that almost exactly accounts for the fluctuations of two small samples, one of which is withdrawn from the totality of the neutrons existing at a given time, while the second is taken from all those that have been absorbed up to that time. The observed counts constitute the sample taken from the absorbed neutron population, while the usual distribution of the whole neutron population is obtained from that of the sampled neutrons by performing a suitable change of variable. According to this interpretation, the neutron distribution so obtained may contain rather large errors, and the only case for which we can say that the approximation is safe is that of the count distribution, provided the detector efficiency is kept very small. Indeed, numerical examples show that the relative errors in most cases are of one or two orders of magnitude larger for the neutron distribution than those for the count distribution.