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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.
R. C. Lloyd, E. D. Clayton, J. H. Chalmers
Nuclear Technology | Volume 4 | Number 3 | March 1968 | Pages 136-141
Technical Paper and Note | doi.org/10.13182/NT68-A26376
Articles are hosted by Taylor and Francis Online.
The results of neutron multiplication measurements performed with arrays of 233U solution apply to criticality safety considerations in handling solutions at a concentration of ≈ 330 g 233U/liter and are useful in checking computational methods. The measurements were made with ≤ 17.3 kg 233U in both reflected and unreflected arrays. Critical numbers of bottles were determined as a function of spacing, and the effect of adding moderating material between the bottles comprising an array was also examined. Monte Carlo calculations were found to reproduce the experimental data reasonably well, with keff being computed to within about 0.03 of unity for those cases compared.
