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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.
D. Ene, J.-C. David, D. Doré, B. Rapp, D. Ridikas
Nuclear Technology | Volume 168 | Number 2 | November 2009 | Pages 513-518
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Accelerators | doi.org/10.13182/NT09-A9235
Articles are hosted by Taylor and Francis Online.
The purpose of this safety study, carried out within the EURISOL Design Study, was to characterize the radiation environment and design the appropriate shielding of the new-generation radioactive ion beam postaccelerator. Both variants of linac layouts - without stripper (L#1) and with stripper (L#2) - were analyzed using the 132Sn25+ radioactive beam of unprecedented intensity, namely, up to [approximately]1013 particles/s, as reference for simulations. In this work two scenarios were analyzed: (a) an accidental full beam loss during 1 s every day and (b) continuous beam loss of 10-4 m-1 , representing normal operation conditions. Representative loss positions along the accelerator at variable energies of 21, 45.5, 76, 115, and 150 MeVu-1 were investigated. The lost ions were assumed to strike a stopping copper target. Dedicated simulations were performed by means of the PHITS code. The induced radioactivity in the accelerator components, concrete walls, and air inside the tunnel were estimated using the DCHAIN-SP-2001 code based on an external neutron source and spallation products derived from PHITS. Ambient dose equivalent rates due to the residual radiation were calculated with the MCNPX code using photon sources resulting from DCHAIN. The effect of implanted radioactive ions at low energies in the accelerator structure was also assessed.
