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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Frisch-Peierls memorandum: A seminal document of nuclear history
The Manhattan Project is usually considered to have been initiated with Albert Einstein’s letter to President Franklin Roosevelt in October 1939. However, a lesser-known document that was just as impactful on wartime nuclear history was the so-called Frisch-Peierls memorandum. Prepared by two refugee physicists at the University of Birmingham in Britain in early 1940, this manuscript was the first technical description of nuclear weapons and their military, strategic, and ethical implications to reach high-level government officials on either side of the Atlantic. The memorandum triggered the initiation of the British wartime nuclear program, which later merged with the Manhattan Engineer District.
Gary R. Smolen, Raymond C. Lloyd, Hideyuki Funabashi
Nuclear Technology | Volume 107 | Number 3 | September 1994 | Pages 304-325
Technical Paper | Nuclear Criticality Safety | doi.org/10.13182/NT94-A35010
Articles are hosted by Taylor and Francis Online.
A series of critical experiments was performed with mixed plutonium-uranium nitrate solutions in two cylinders and in a variable thickness slab tank. The solution concentrations ranged from 12 to 174 g Pu/ℓ with Pu/Pu+U ratios of 0.5, 0.4, and 0.2. The criticality data were used to validate two versions of the SCALE computer code system (SCALE-4 and SCALE-2). Calculations were performed with the 27-energy-group cross-section library, derived from the Evaluated Nuclear Data File B-Version IV. The average calculated keff for all geometries (39 experiments) is 1.006 (σ = 0.006), calculated with SCALE-4, and 1.004 (σ = 0.007), calculated with SCALE-2. Overall, the range of calculated keff varied from 0.989 to 1.019. These experiments covered a wide range of parameters, with variations in physical, chemical, and neutronic parameters.
