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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NRC’s hybrid AI workshop coming up
The Nuclear Regulatory Commission will host a hybrid public workshop on September 24 from 9 a.m.-5 p.m. Eastern time to discuss its activities for the safe and secure use of artificial intelligence in NRC-regulated activities.
J. M. Pearson
Nuclear Technology | Volume 210 | Number 6 | June 2024 | Pages 1078-1082
Note | doi.org/10.1080/00295450.2023.2274690
Articles are hosted by Taylor and Francis Online.
The Frisch-Peierls memorandum of March 1940 opened the way to nuclear weapons through its conclusion that the critical mass for an explosive chain reaction in 235U could be as small as 0.6 kg. This gross underestimate was based on the conjecture that the cross section for the fission of 235U with fast neutrons was 10 barns. Though this value turned out to be far too high, it is argued here that the choice made was not unreasonable at the time.