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Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Nuclear Science and Engineering
December 2025
Nuclear Technology
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November 2025
Latest News
Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
Alexis Jinaphanh, Giorgio Valocchi, Andrea Zoia
Nuclear Science and Engineering | Volume 199 | Number 1 | April 2025 | Pages S406-S434
Research Article | doi.org/10.1080/00295639.2024.2323225
Articles are hosted by Taylor and Francis Online.
In this paper, we describe the implementation, verification, and numerical validation of Generalized Perturbation Theory (GPT) capabilities in the TRIPOLI4® Monte Carlo code. The GPT is applied to reaction rate ratios (linear forms) and effective kinetics parameters (bilinear forms). For these latter, we focus in particular on the effective neutron generation time Λeff, the effective prompt lifetime ℓeff, and the effective delayed neutron fraction βeff. Verification is achieved comparing the results obtained using TRIPOLI-4® to benchmarks where analytical solutions are available. Numerical validation is performed with respect to independent Monte Carlo calculations using the SCALE 6.2.4 and SERPENT 2.2 codes, to published results, and to direct perturbations. Finally, a comparison with respect to the APOLLO3® deterministic code is performed for the EPICURE experimental configuration of the water-moderated EOLE reactor core, formerly operated at CEA.
