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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Chris Wagner: The role of Eden Radioisotopes in the future of nuclear medicine
Chris Wagner has more than 40 years of experience in nuclear medicine, beginning as a clinical practitioner before moving into leadership roles at companies like Mallinckrodt (now Curium) and Nordion. His knowledge of both the clinical and the manufacturing sides of nuclear medicine laid the groundwork for helping to found Eden Radioisotopes, a start-up venture that intends to make diagnostic and therapeutic raw material medical isotopes like molybdenum-99 and lutetium-177.
Kazuo Shin, Hideo Hirayama
Nuclear Science and Engineering | Volume 118 | Number 2 | October 1994 | Pages 91-102
Technical Paper | doi.org/10.13182/NSE94-A28538
Articles are hosted by Taylor and Francis Online.
A new approximate expression for gamma-ray buildup factors of multilayered shields is proposed. The expression is formulated based on the vector form and considers the gamma-ray energy spectrum directly. It treats the gamma-ray transmission by a transmission matrix and the backscattering by an albedo matrix. Its capability of reproducing the buildup factors for multilayered shields is demonstrated by using double-layered shields composed of two materials of water, iron, and lead at 1 and 10 MeV. The data of three-layered shields of these materials are also very well reproduced. The mechanism of the density effect arising, which appears in the buildup factor for a point isotropic source, is clearly interpreted by the current method to be a geometrical effect. A correction factor for incorporating the density effect into the current expression is derived. The modified expression is successfully applied to buildup factors for a 0.5-MeV point isotropic source for two-layered shields of water and iron.