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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
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.
Weston M. Stacey
Fusion Science and Technology | Volume 36 | Number 1 | July 1999 | Pages 38-46
Technical Paper | doi.org/10.13182/FST99-A89
Articles are hosted by Taylor and Francis Online.
A linear analysis of thermal instabilities along the magnetic field lines in the plasma edge is used to derive predictive algorithms for the edge density limit for the onset of multifaceted asymmetric radiation from the edge (MARFE) within the last closed flux surface in tokamaks. Calculated MARFE onset density limits for representative impurity and recycling neutral concentrations and representative edge plasma parameters in a model problem exhibit the expected strong dependence on impurity type and concentration at low recycling neutral concentrations. At recycling neutral concentrations greater than ~1 × 10-5, the MARFE onset density limit is found to depend strongly on the recycling neutral concentration and to be relatively independent of impurity type or concentration. Predicted MARFE onset density limits for two DIII-D shots agree reasonably well with experimental data.
