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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
Radiant to build first microreactor at Tenn. Manhattan Project site
Radiant Industries will build its first portable nuclear reactor at the site of the Manhattan Project in Oak Ridge, Tenn.
The land for Radiant’s new factory includes portions of the K-27 and K-29 Manhattan Project sites. The company plans to test Kaleidos, a 1-MW nuclear microreactor, in 2026, with first deployments expected soon after.
Yoshiko Harima, Hideo Hirayama
Nuclear Science and Engineering | Volume 113 | Number 4 | April 1993 | Pages 367-378
Technical Paper | doi.org/10.13182/NSE92-52
Articles are hosted by Taylor and Francis Online.
Exposure buildup factors, energy spectra, and angular flux distributions for plane-normal incident and point isotropic source gamma rays of 0.1, 0.5, 1, 3, 6, and 10 MeV penetrating two-layer water-lead and lead-water shields are calculated with the point Monte Carlo code EGS4 The effects of bremsstrahlung and fluorescent radiation are included. The value of the buildup factor in the second layer lies between those for infinite media of both materials in two source geometries in the 0.5- to 3-MeV energy range. However, this behavior varies remarkably and is enhanced with a bremsstrahlung contribution, when the source energy is higher than that corresponding to the minimum in the attenuation coefficient of lead. This varies equally with the fluorescent contribution when the source energy is close to the K edge of lead.