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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.
V. Ya. Goloborod'ko, Ya. I. Kolesnichenko, S. N. Reznik, V. A. Yavorskij
Fusion Science and Technology | Volume 25 | Number 3 | May 1994 | Pages 249-257
Technical Paper | Alpha-Particle Special / Plasma Engineering | doi.org/10.13182/FST94-A30281
Articles are hosted by Taylor and Francis Online.
A kinetic equation is derived for the neoclassical distribution function of alpha particles with orbits intersecting or approaching the magnetic axis of a tokamak. This equation takes into account both the collisional slowing down and the pitch-angle scattering of alpha particles. An equation with a simplified pitchangle scattering term is solved analytically, and the distribution function obtained is used to find the alpha-particle bootstrap current at the magnetic axis. It is shown that the pitch-angle scattering leads to an alpha-particle current in the near-axis region that is larger than the one predicted from early neoclassical theory, which allows only for the slowing down of alpha particles.
