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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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NN Asks: What did you learn from ANS’s Nuclear 101?
Mike Harkin
When ANS first announced its new Nuclear 101 certificate course, I was excited. This felt like a course tailor-made for me, a transplant into the commercial nuclear world. I enrolled for the inaugural session held in November 2024, knowing it was going to be hard (this is nuclear power, of course)—but I had been working on ramping up my knowledge base for the past year, through both my employer and at a local college.
The course was a fast-and-furious roller-coaster ride through all the key components of the nuclear power industry, in one highly challenging week. In fact, the challenges the students experienced caught even the instructors by surprise. Thankfully, the shared intellectual stretch we students all felt helped us band together to push through to the end.
We were all impressed with the quality of the instructors, who are some of the top experts in the field. We appreciated not only their knowledge base but their support whenever someone struggled to understand a concept.
D. C. Hunt, D. C. Coonfield
Nuclear Technology | Volume 12 | Number 3 | November 1971 | Pages 260-268
Technical Paper | Reactor | doi.org/10.13182/NT71-A31005
Articles are hosted by Taylor and Francis Online.
The effects of varying energy group cross-section sets and the space-angle mesh must be understood to evaluate critical parameters computed by the discrete ordinates Sn method. In this paper, these effects are investigated using critical mass calculations on several enriched uranium metal systems. Based on the variation of critical mass with refinement of the space-angle mesh, mesh specification criteria are deduced. The most significant criteria established for these systems is that Sn (n ≥ 16) calculations are required. Next, the literature on fast (En ≥ 3 keV) 235U and 238U neutron cross sections is reviewed and a seven-group cross-section set in this energy range is developed. This fast set is found to reproduce to within 0.5% the measured critical masses of several fast uranium systems. Finally, group cross-section sets in the resolved resonance energy ranges of 235 U and 238U are developed according to several energy self-shielding models. A recommended set is obtained by interpolation between two of these models. This set yields critical masses in good agreement with observed critical masses for several intermediate energy metal critical systems with several 235U enrichments.
