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Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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ANS Student Conference 2025
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Albuquerque, NM|The University of New Mexico
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Nuclear News 40 Under 40 discuss the future of nuclear
Seven members of the inaugural Nuclear News 40 Under 40 came together on March 4 to discuss the current state of nuclear energy and what the future might hold for science, industry, and the public in terms of nuclear development.
To hear more insights from this talented group of young professionals, watch the “40 Under 40 Roundtable: Perspectives from Nuclear’s Rising Stars” on the ANS website.
Helmut Kunze
Nuclear Science and Engineering | Volume 23 | Number 1 | September 1965 | Pages 90-97
Technical Paper | doi.org/10.13182/NSE65-A19262
Articles are hosted by Taylor and Francis Online.
For the heavy-gas model, the stationary space-dependent neutron spectrum in one- and two-dimensional heterogeneous thermal reactors is determined in the diffusion approximation. The fuel elements, which are not necessarily identical, and absorbing slabs or rods are arranged arbitrarily. However, absorption in all of them is assumed to follow a l/v law. The neutron flux is represented as a linear combination of the lowest eigenfunction of the Laplace operator for the geometry considered and a finite set of Green's functions for the stationary-wave equation for various, usually imaginary, wave numbers. The energy-dependent coefficients are determined by the author's method, developed in an earlier paper. The lowest eigenfunctions of the Laplace operator and Green's functions for the stationary-wave equation are given for some geometries of practical interest. Solutions found earlier for simple geometries may now be regarded as special representations of these Green's functions. But in these cases, too, other representations can be found which are to be preferred for numerical reasons.