ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
S. G. Carpenter
Nuclear Science and Engineering | Volume 21 | Number 4 | April 1965 | Pages 429-440
Technical Paper | doi.org/10.13182/NSE65-A18787
Articles are hosted by Taylor and Francis Online.
Reactivity effects of various materials of interest to epithermal and fast reactors have been measured in a series of neutron spectra with median energies of neutrons causing fission ranging from 422 keV to 8.5 eV. An oscillator technique capable of sensitivities of 10−8 Δk was used. In addition, a power-history or ‘reactivity-vs-time’ method has been developed for fast but less sensitive reactivity measurements. It has been used to obtain radial reactivity traverses and rod calibrations and for other routine reactivity measurements.
