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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.
Hubert Pialot, David Demange, Brice Ravat, Manuel Grivet
Fusion Science and Technology | Volume 41 | Number 3 | May 2002 | Pages 495-499
Analysis and Monitoring | Proceedings of the Sixth International Conference on Tritium Science and Technology Tsukuba, Japan November 12-16, 2001 | doi.org/10.13182/FST02-A22638
Articles are hosted by Taylor and Francis Online.
This paper presents a method to quantify the tritium activity in a drum by measurement of its helium-3 leak. A model of helium exchanges with the atmosphere has been developed. It takes into account the diffusion phenomena and the influence of atmospheric pressure changes. The validation has been achieved with a pilot and the comparison between theoretical and experimental data has highlighted a very good agreement. Drum's helium-3 leak equilibrates after six months and then equals the helium-3 production in the drum and so to the total tritium activity. The measurement technique is also described. It's based on quantitative helium trace level determinations with an adapted leak detector. After a drum's confinement period of 5 hours and a cryogenic treatment of gaseous samples, the method allows to detect a 5 GBq activity of tritium in a drum.