ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
H. A. Larson, J. I. Sackett
Nuclear Technology | Volume 33 | Number 2 | April 1977 | Pages 223-230
Technical Paper | Instrument | doi.org/10.13182/NT77-A31779
Articles are hosted by Taylor and Francis Online.
An Experimental Breeder Reactor II (EBR-II) anomalous reactivity meter was examined to verify its feasibility as a useful device in a fast reactor system. Anomalous reactivity is calculated by comparing “measured” reactivity with that predicted by system parameters; this provides useful diagnostic, alarm, and possible plant protective functions. Examples include application during an arbitrary rise-to-power for EBR-II as well as effectiveness during an EBR-II loss-of-primary -pumping-power event. Single subassembly flow loss events may be questionable for the crude anomalous reactivity meter described here, but flow disturbances of the magnitude required for this event have been observed with a reactivity meter.
