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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 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.
B. Basoglu, R. W. Brewer, C. F. Haught, D. F. Hollenbach, A. D. Wilkinson, H. L. Dodds, P. F. Pasqua
Nuclear Technology | Volume 105 | Number 1 | January 1994 | Pages 14-30
Technical Paper | Special on Nuclear Criticality Safety / Nuclear Criticality Safety | doi.org/10.13182/NT94-A34907
Articles are hosted by Taylor and Francis Online.
This paper describes the development of a computer model for predicting the excursion characteristics of a postulated, hypothetical, criticality accident involving a homogeneous mixture of low-enriched UO2 powder and water contained in a cylindrical blender. The model uses point neutronics coupled with simple lumped-parameter thermal-hydraulic feedback. The temperature of the system is calculated using a simple time-dependent energy balance where two extreme conditions for the thermal behavior of the system are considered, which bound the real life situation. Using these extremes, three different models are developed. To evaluate the models, we compared our results with the results of the POWDER code, which was developed by the Commissariat à l’Energie Atomique/United Kingdom Atomic Energy Authority (CEA/UKAEA) for damp powder systems. The agreement in these comparisons is satisfactory. Results of the excursion studies in this work show that approximately 1019 fissions occur as a result of accidental water ingress into powder blenders containing 5000 kg of low-enriched (5%) UO2 powder.
