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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.
F. Warmer, C. D. Beidler, A. Dinklage, Y. Turkin, R. Wolf
Fusion Science and Technology | Volume 68 | Number 4 | November 2015 | Pages 727-740
Technical Paper | doi.org/10.13182/FST15-131
Articles are hosted by Taylor and Francis Online.
In fusion power plant studies, a high confinement improvement with respect to empirical scaling is often assumed in the design of compact machines. In this work, the limits of such a confinement enhancement are studied for a helical-axis advanced stellarator (HELIAS).
As a first exercise, the well-established power balance approach is used to investigate the impact of confinement enhancement (in terms of the ISS04 renormalization factor) on the required size of HELIAS power plants. It is found that both a lower (0.5) and an upper limit (1.5 to 1.7) exist for which, respectively, ignition is no longer possible or further confinement enhancement irrelevant due to physics limits.
In the second part of the work, a predictive neoclassical transport model is introduced and employed to determine a self-consistent confinement time based on transport modelling. It is found that the confinement enhancement with respect to the ISS04 scaling decreases in comparison to Wendelstein 7-X as the device is scaled to reactor size, dropping from ~2.5 to a range of 1.2 to 1.3. This behavior is explained with underlying scaling relations and transport effects. The results from both models are consistent and important for future HELIAS systems studies.