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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.
Dan M. Goebel, Joseph Bohdansky, Robert W. Conn, Yoshi Hirooka, Wai Kwong Leung, Richard E. Nygren, George R. Tynan
Fusion Science and Technology | Volume 15 | Number 1 | January 1989 | Pages 102-107
Technical Paper | doi.org/10.13182/FST89-A25332
Articles are hosted by Taylor and Francis Online.
The results of erosion and redeposition studies of graphite by hydrogen plasma bombardment in the PISCES facility are reviewed. The total erosion yields of several types of graphites have been measured during plasma exposure with ion fluxes of up to 2 × 1018 cm−2·s−1, ion energies of 50 to 200 eV, and sample temperatures of 50 to 950°C. Hydrogen and deuterium plasmas have been used to bombard Poco, ATJ, and pyrolytic graphites, and a “four-directional” carbon-carbon (C-C) composite weave. The erosion rates of all the graphites tested are about equal, suggesting that surface damage by the ion bombardment results in similar erosion yields. The C-C composite weave material showed an increased weight loss during initial exposure, and then equal or lower erosion yields compared to the other graphites. Graphite has a strong ion energy dependence in the maximum chemical erosion yield at a temperature of 500 to 600°C and no energy dependence for the erosion at room temperature. At temperatures above 800°C, the chemical erosion is suppressed and the erosion yield reaches values expected for physical sputtering with thresholds of ∼40 eV for both hydrogen and deuterium. The measured erosion rates demonstrate that chemical sputtering is not significantly suppressed by high-ion fluxes. The net erosion is also reduced by reionization in the plasma and redeposition of hydrocarbons and physically sputtered carbon.