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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.
O. Ågren, V. E. Moiseenko (21R02)
Fusion Science and Technology | Volume 51 | Number 2 | February 2007 | Pages 200-203
Technical Paper | Open Magnetic Systems for Plasma Confinement | doi.org/10.13182/FST07-A1350
Articles are hosted by Taylor and Francis Online.
The straight field line mirror field is the unique field which gives the lowest ellipticity of the flux tube of an MHD stable minimum B mirror field. In this particular vacuum field, each gyro center bounces back and forth on a single magnetic field line, and a pair of two new constants of motion is associated with this property. Using these invariants in the Vlasov equation, it can be shown that the radial gyro center magnetic drift is absent to first order in the plasma beta, and the equilibrium is omnigenous. The neoclassical increase of the radial transport may thus be avoided without an axisymmetrization of this single cell mirror.A scheme to improve end confinement of ions, and simultaneously create an electric potential barrier for the electrons and a sloshing ion component, has been proposed. The end plugging transforms ions under way to escape into the loss cone into sloshing ions by ion cyclotron resonance heating. Numerical studies on sloshing ion production by RF heating demonstrate strong absorption of the RF field near the fundamental gyro frequency resonance of the minority deuterium ions as well as near the tritium second harmonic gyro frequency resonance. The scenario indicates a possibility to achieve a high energy gain factor in this kind of single cell mirror with the proposed modified thermal barrier.