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Breaking ground on a new approach to construction
The drive to Kairos Power’s reactor demonstration site in Oak Ridge, Tenn., is not only scenic—it’s historic. Nearly 85 years ago, roughly 30,000 construction workers transformed orchards and farmland into a key Manhattan Project site. Depending on your route, you may pass by one of the three gatehouses that were once military checkpoints controlling access to Atomic Energy Commission production facilities.
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.