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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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.
N. Rice, M. Vu, C. Kong, M. Mauldin, A. Tambazidis, M. Hoppe, Jr., P. Fitzsimmons, M. Farrell, D. Clark, E. Dewald, V. Smalyuk
Fusion Science and Technology | Volume 73 | Number 2 | March 2018 | Pages 279-284
Technical Paper | doi.org/10.1080/15361055.2017.1389603
Articles are hosted by Taylor and Francis Online.
Capsule drive in National Ignition Facility indirect-drive implosions is generated by X-ray illumination from cylindrical hohlraums. The cylindrical hohlraum geometry is axially symmetric but not spherically symmetric, causing capsule–fuel drive asymmetries. It is hypothesized that fabricating capsules asymmetric in wall thickness (shimmed) may compensate for drive asymmetries and improve implosion symmetry. Simulations suggest that for high-compression implosions, Legendre mode P4 hohlraum flux asymmetries are the most detrimental to implosion performance.
General Atomics has developed a diamond-turning method to form a glow discharge polymer capsule outer surface to a Legendre mode P4 profile. The P4 shape requires full capsule surface coverage. As a result, in order to avoid tool-lathe interference, flipping the capsule part way through the machining process is required. This flipping process risks misalignment of the capsule, causing a vertical step feature on the capsule surface. Recent trials have proven this step feature height can be minimized to ~0.25 µm.