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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Feroz Ahmed, A. K. Ghatak
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 106-118
Technical Paper | doi.org/10.13182/NSE68-A20922
Articles are hosted by Taylor and Francis Online.
We report the results of some calculations of the fundamental mode decay constant (and the corresponding eigenfunction) of the neutron transport operator in slabs and spheres of various sizes. The assemblies are assumed to be homogeneous and nonmultiplying with absorption cross section varying as 1/v. The scattering is assumed to be isotropic in the laboratory system, and parameters are chosen to represent the scattering by beryllium. The integral equations were solved by the multigroup technique, and calculations show that the fundamental mode eigenvalue for a slab is bounded by (v ∑)min whereas no bound exists for a spherical assembly. The solutions wherever possible are compared with the corresponding exp(iBx) theory results, and the implications for experiments are discussed. The nonseparability of the energy and space dependence of the asymptotic flux has been shown explicitly, and its consequences on the extrapolation distance have been pointed out.