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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
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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.
K. Tobita, Y. Kusama, K. Shinohara, T. Nishitani, H. Kimura, G. J. Kramer, M. Nemoto, T. Kondoh, T. Oikawa, A. Morioka, K. Hamamatsu, S. Wang, S. Takeji, M. Takechi, M. Ishikawa, K. Tani, M. Saigusa, T. Ozeki
Fusion Science and Technology | Volume 42 | Number 2 | September-November 2002 | Pages 315-326
Technical Paper | doi.org/10.13182/FST02-A231
Articles are hosted by Taylor and Francis Online.
Energetic particle experiments in JT-60U are summarized, mainly covering ripple loss and Alfvén eigenmodes (AE modes). Significant loss was observed for 85 keV neutral beam injected (NBI) ions and fusion-produced tritons as toroidal field ripple at the plasma surface increased, especially in a reversed shear plasma. Measurement of hot spots on the first wall due to ripple loss confirmed agreement with code predictions, validating the modeling incorporated in an orbit-following Monte Carlo code. A variety of AE modes were destabilized in ion cyclotron range of frequencies (ICRF) minority heating and negative-ion-based NBI (N-NBI) heating. Most of the observed modes are gap modes identified to be toroidicity-induced, ellipticity-induced, and triangularity-induced AE modes. An interesting finding is pulsating modes accompanying frequency sweep, which were destabilized by N-NBI and sometimes induced a beam ion loss of up to 25%. Also presented are energetic particle issues in auxiliary heating with ICRF and N-NBI.