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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
Latest News
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.
Josep Maria Fontdecaba, Francisco Castejón, Rosa Balbín, Daniel López-Bruna, Sergei Yakovlevich Petrov, Ferran Albajar, Guillem Cortés, Javier Dies, Jerónimo García, Jesus Izquierdo, Joan Fontanet
Fusion Science and Technology | Volume 46 | Number 2 | September 2004 | Pages 271-278
Technical Papers | Stellarators | doi.org/10.13182/FST04-A565
Articles are hosted by Taylor and Francis Online.
Energy-resolved neutral particle fluxes are studied in the TJ-II stellarator by using measurements from a neutral particle analyzer. The average ion energy can be deduced up to positions outside the last closed magnetic surface because of an upgrade of the diagnostic. The results suggest that the average ion energy profile is flat, even at positions outside the last closed magnetic surface, which implies the existence of hot ions well outside the plasma. Such a flat profile may be related to wide ion orbits connecting distant areas of the plasma.
