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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.
R. Keppens
Fusion Science and Technology | Volume 53 | Number 2 | February 2008 | Pages 135-143
Technical Paper | Equilibrium and Instabilities | doi.org/10.13182/FST08-A1699
Articles are hosted by Taylor and Francis Online.
The ideal MagnetoHydroDynamic (MHD) equations accurately describe the macroscopic dynamics of a perfectly conducting plasma. Adopting a continuum, single fluid description in terms of the plasma density , velocity v, thermal pressure p and magnetic field B, the ideal MHD system expresses conservation of mass, momentum, energy, and magnetic flux. This nonlinear, conservative system of 8 partial differential equations enriches the Euler equations governing the dynamics of a compressible gas with the dynamical influence - through the Lorentz force - and evolution - through the additional induction equation - of the magnetic field B. In multi-dimensional problems, the topological constraint expressed by the Maxwell equation B = 0, represents an additional complication for numerical MHD. Basic concepts of shock-capturing high-resolution schemes for computational MHD are presented, with an emphasis on how they cope with the thight physical demands resulting from nonlinearity, compressibility, conservation, and solenoidality.