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Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Nicholas Tsoulfanidis—ANS member since 1969
We welcome ANS members who have careered in the community to submit their own Nuclear Legacy stories, so that the personal history of nuclear power can be captured. For information on submitting your stories, contact nucnews@ans.org.
As an undergraduate I studied physics at the University of Athens. I entered the university in 1955 after successfully passing a national exam (came up fourth in a field of about 700 candidates). Upon graduation and finishing my mandatory two-year military service, the plan was to teach physics either in a public high school or as a tutor for a private for-profit institution, preparing high school students for the national exam.
Thomas A. Chadwick, M. B. Chadwick
Nuclear Technology | Volume 207 | Number 1 | December 2021 | Pages S356-S373
Critical Review | doi.org/10.1080/00295450.2021.1903300
Articles are hosted by Taylor and Francis Online.
The Christy Gadget is the informal name for the plutonium device detonated in the Trinity test on July 16, 1945. In September 1944, Robert Christy, working in the theoretical implosion group, proposed a novel concept that altered the design of the nuclear core in Fat Man. While scientists originally intended to use a hollow sphere of plutonium, this design entailed substantial risk due to the likelihood of asymmetries resulting from implosion. Christy proposed changing the design to a solid sphere of plutonium with a modulated neutron source, and the design was eventually adopted, tested at Trinity, and used in the attack on Nagasaki. While there is no question regarding the important role that Christy played in demonstrating its feasibility as a reliable design, there is a debate as to who initially proposed the idea; though most sources have attributed this invention to Christy, some historical sources have attributed credit to Christy’s group leader, Rudolf Peierls, or indeed other scientists. This paper seeks to outline and resolve this dispute. We present new unclassified evidence extracted from previously unavailable sources (to unclassified audiences) from the National Security Research Center archives at Los Alamos National Laboratory. This evidence consists of 1945–1946 patent documentation, oral history interview tapes of Christy and Peierls, and monthly 1944 progress reports from the Theoretical Division. Though Christy and Peierls share joint credit on the patent, both Christy’s and Peierls’ words and writings, together with sources from Hans Bethe and Edward Teller, support the traditional view that Christy was indeed the originator of the idea. While Christy does deserve the majority of the credit for the invention and design, we acknowledge the important role Peierls and von Neumann played in its development.