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TerraPower announces second Ac-225 production facility
TerraPower Isotopes, a TerraPower subsidiary, plans to increase its actinium-225 production 20-fold by opening a new manufacturing facility in Philadelphia, Pa., and by expanding the capacity of its Everett, Wash., facility. On March 17, TerraPower Isotopes said it expects the new facility to begin producing the medical radioisotope for targeted alpha therapy in 2029.
Taro Ueki, J. E. Hoogenboom, J. L. Kloosterman
Nuclear Science and Engineering | Volume 137 | Number 2 | February 2001 | Pages 117-145
Technical Paper | doi.org/10.13182/NSE01-A2180
Articles are hosted by Taylor and Francis Online.
In Monte Carlo correlated coupling, forward and adjoint particle histories are initiated in exactly opposite directions at an arbitrarily placed surface between a physical source and a physical detector. It is shown that this coupling calculation can become more efficient than standard forward calculations. In many cases, the basic form of correlated coupling is less efficient than standard forward calculations. This inherent inefficiency can be overcome by applying a black absorber perturbation to either the forward or the adjoint problem and by processing the product of batch averages as one statistical entity. The usage of the black absorber is based on the invariance of the response flow integral with a material perturbation in either the physical detector side volume in the forward problem or the physical source side volume in the adjoint problem. The batch-average product processing makes use of a quadratic increase of the nonzero coupled-score probability. All the developments have been done in such a way that improved efficiency schemes available in widely distributed Monte Carlo codes can be applied to both the forward and adjoint simulations. Also, the physical meaning of the black absorber perturbation is interpreted based on surface crossing and is numerically validated. In addition, the immediate reflection at the intermediate surface with a controlled direction change is investigated within the invariance framework. This approach can be advantageous for a void streaming problem.