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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
Senate EPW Committee to hold Nieh nomination hearing
Nieh
The Senate Environment and Public Works Committee will hold a nomination hearing Wednesday for Ho Nieh, President Donald Trump’s nominee to serve as commission at the Nuclear Regulatory Commission.
Trump nominated Nieh on July 30 to serve as NRC commissioner the remainder of a term that will expire June 30, 2029, as Nuclear NewsWire previously reported.
Nieh has been vice president of regulatory affairs at Southern Nuclear since 2021, though since June 2024 he has been at the Institute of Nuclear Power Operations as a loaned executive.
A return to the NRC: If confirmed by the Senate, Nieh would be returning to the NRC after three previous stints totaling nearly 20 years.
Nicolas Authier, Benoît Richard, Philippe Humbert
Nuclear Science and Engineering | Volume 177 | Number 2 | June 2014 | Pages 169-183
Technical Paper | doi.org/10.13182/NSE12-111
Articles are hosted by Taylor and Francis Online.
We provide experimental data on the initiation of persistent fission chains obtained at different supercritical states, using the fast burst reactor Caliban. In many previous papers, theory has been compared mostly with initiation experiments at various superprompt critical states, whereas very few experimental data have been published on delayed supercritical states. To fill the lack of data, we have conducted three studies on the reactor at reactivities far below 0.7 $, which is one of the lowest states ever published for a similar assembly. We give a justification of the use of the gamma function to fit experimental results for the temporal distributions of waiting times and compare experiments with numerical simulations obtained with a punctual zero-dimensional Monte Carlo code and a punctual deterministic initiation code.