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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
S. Aoyama, Y. Miyazawa, K. Ogura, A. Sugawara, M. Hirata (19P40)
Fusion Science and Technology | Volume 51 | Number 2 | February 2007 | Pages 325-327
Technical Paper | Open Magnetic Systems for Plasma Confinement | doi.org/10.13182/FST07-A1390
Articles are hosted by Taylor and Francis Online.
We improve the performance of the K-band oversized backward wave oscillator. The beam is annular and weakly relativistic. The beam voltage is less than 100 kV and the beam current is less than 500 A. The operation frequencies are in the range of 23-27 GHz. The electromagnetic field of the K-band BWO concentrates in the vicinity of the SWS wall and the electron beam should be propagated within a few mm from the wall. The uniformity of annular beam is also very important for the efficient beam coupling. First, we modify the oversized SWS so that the beam interaction point is shifted to the point. Secondly, we improve uniformity of the annular electron beam and the output power increases up to about 500 kW level.
