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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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My story: Stanley Levinson—ANS member since 1983
Levinson early in his career and today.
As a member of the American Nuclear Society, I have been to many conferences. The International Conference on Probabilistic Safety Assessment and Analysis (PSA ’25), embedded in ANS Annual Meeting in Chicago in June, held special significance for me with the PSA ’25 opening plenary session recognizing the 50th anniversary of the publication of WASH-1400, which helped define my career. Reflecting on that milestone sent me back to 1975, when I was just an undergraduate student studying nuclear engineering at Rensselaer Polytechnic Institute (RPI) in Troy, N.Y., focusing on my mechanics, fluids, and thermodynamic classes as well as my first set of nuclear engineering classes. At that time—and many times since—the question “Why nuclear engineering?” was raised.
V. Spiegel
Nuclear Science and Engineering | Volume 53 | Number 3 | March 1974 | Pages 326-327
Technical Note | doi.org/10.13182/NSE74-A23358
Articles are hosted by Taylor and Francis Online.
The effective half-life of 252Cf has been determined as 2.638 ± 0.007 yr. The method utilized the ratio of the manganese activity induced in a manganous-sulfate bath by a 252Cf spontaneous-fission neutron source and the National Bureau of Standards photo-neutron source to measure the change in emission rate of the 252Cf source over a period of 1.77 half-lives. The data were corrected for the activity of radium (1622-yr half-life) in the photoneutron source (-0.2%) and for the competing neutron production from 250Cf.
