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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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PR: American Nuclear Society welcomes Senate confirmation of Ted Garrish as the DOE’s nuclear energy secretary
Washington, D.C. — The American Nuclear Society (ANS) applauds the U.S. Senate's confirmation of Theodore “Ted” Garrish as Assistant Secretary for Nuclear Energy at the U.S. Department of Energy (DOE).
“On behalf of over 11,000 professionals in the fields of nuclear science and technology, the American Nuclear Society congratulates Mr. Garrish on being confirmed by the Senate to once again lead the DOE Office of Nuclear Energy,” said ANS President H.M. "Hash" Hashemian.
Valerio Mascolino, Alireza Haghighat
Nuclear Science and Engineering | Volume 198 | Number 3 | March 2024 | Pages 592-627
Research Article | doi.org/10.1080/00295639.2023.2197844
Articles are hosted by Taylor and Francis Online.
The available three-dimensional (3-D), time-dependent neutron transport algorithms and codes (deterministic or Monte Carlo) are very computationally intensive and are impractical for the simulation of real-world reactors. Henceforth, commonly approximate forms of the transport equation (e.g., diffusion or SPn) are used with expected loss of accuracy. We have developed a hybrid deterministic and Monte Carlo algorithm that not only preserve a Monte Carlo–level accuracy but can achieve a solution in seconds or minutes. This algorithm has been incorporated into the RAPID code system and tested for a number of benchmark problems. This novel time-dependent algorithm, referred to as tRAPID, utilizes a transient fission matrix methodology and allows for fast and accurate simulation of 3-D time-dependent neutron transport problems. The tRAPID algorithm is used to calculate neutron kinetics parameters (such as and Rossi-) and 3-D time-dependent prompt and delayed fission source distributions for two reference models: the Flattop-Pu critical assembly and the Jožef Stefan Institute TRIGA Mark-II benchmark core. Results are compared to experiments reported in the International Criticality Safety Benchmark Evaluation Project Handbook as well as to a reference Serpent Monte Carlo calculation. The tRAPID results are in excellent agreement with both the experimental data and Serpent predictions, while requiring minimal computing resources.