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Westinghouse, Nordion, and PSEG team up to produce Co‑60 in the United States
This past January, Westinghouse Electric Company, Nordion, and PSEG Nuclear formalized agreements to implement newly developed cobalt-60 production technology at Units 1 and 2 of PSEG’s Salem nuclear power plant in New Jersey, with the Co-60 to be supplied to Nordion. Through an ongoing joint initiative, the companies aim to harness U.S. pressurized water reactors to produce a key medical isotope and build the first commercial-scale Co-60 production platform in the United States.
W. F. Miller, Jr., Wm. H. Reed
Nuclear Science and Engineering | Volume 62 | Number 3 | March 1977 | Pages 391-411
Technical Paper | doi.org/10.13182/NSE62-391
Articles are hosted by Taylor and Francis Online.
Using projection operators, we rederive x-y geometry discrete ordinates-to-spherical harmonics (SN → PN-1.) fictitious sources defined in the literature as ray-effect mitigating devices. We define a new x-y geometry fictitious source with certain properties that are superior to earlier sources. A detailed description of the S2 → P1 source, including a discussion of vacuum and reflective boundary conditions, is provided. We then derive fictitious sources in r-z geometry that give spherical harmonics and spherical-harmonics-like solutions. Finally, a simple algorithm is presented that allows a significant reduction in the iteration time needed to obtain ray-effect-free solutions. This algorithm effectively reduces the size of the fictitious source in energy groups where ray-effect distortions are not expected. The new sources and the algorithm for reduction of computation time make this approach viable for solving the ray-effect problem.