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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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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My Story: John L. Swanson—ANS member since 1978
. . . and in 2019, on his 90th birthday.
Swanson in 1951, the year of his college graduation . . .
My pre-college years were spent in a rural suburb of Tacoma, Wash. In 1947, I enrolled in Reed College, a small liberal arts school in Portland, Ore.; I majored in chemistry and graduated in 1951. While at Reed, I met and married a young lady with whom I would raise 3 children and spend the next 68 years of my life—almost all of them in Richland, Wash., where I still live.
I was fortunate to have a job each of my “college summers” that provided enough money to cover my college costs for the next year; I don’t think that is possible these days. My job was in the kitchen/dining hall of a salmon cannery in Alaska. Room and board were provided and the cannery was in an isolated location, so I could save almost every dollar of my salary.
H. Naik, S. P. Dange, R. J. Singh, W. Jang
Nuclear Science and Engineering | Volume 196 | Number 7 | July 2022 | Pages 824-851
Technical Paper | doi.org/10.1080/00295639.2021.2025298
Articles are hosted by Taylor and Francis Online.
Mass chain yield distribution has been done in the thermal neutron–induced fission of 239Pu by measuring the cumulative yields of various fission products within the mass range of 78 to 159 and the independent yields of a few products. An off-line gamma-ray spectrometric technique was used to measure the gamma-ray activities of the fission products. From the measured values of the cumulative yields, the post-neutron mass chain yield distribution was obtained after applying the charge distribution correction. Data from the present and earlier work of our laboratory in the 239Pu(nth,f) reaction were compared with similar data of 238,241Pu(nth,f) and 240Pu(n,f) reactions, and it was found that the fine structures of the mass yield distributions are similar. The mass yield distribution in the 239Pu(nth,f) reaction was also compared with those of 229Th(nth,f) and 252Cf(SF) reactions to examine the effect of charge and mass difference of the fissioning systems on the mass yield distribution. It was found that the asymmetric standard I mode of fission is favorable in the 238,239,241Pu(nth,f) and 240Pu(n,f) reactions whereas the standard II mode is favorable in the 229Th(nth,f) and 252Cf(SF) reactions.
