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.
Explore membership for yourself or for your organization.
Conference 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!
Latest Magazine Issues
Aug 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
Fusion Science and Technology
August 2025
Latest News
IAEA program uses radioisotopes to protect rhinos
After two years of testing, the International Atomic Energy Agency and the University of the Witwatersrand in Johannesburg, South Africa, have begun officially implementing the Rhisotope Project, an innovative effort to combat rhino poaching and trafficking by leveraging nuclear technology.
Stanley C. Fultz
Nuclear Science and Engineering | Volume 6 | Number 4 | October 1959 | Pages 313-319
Technical Paper | doi.org/10.13182/NSE59-A28850
Articles are hosted by Taylor and Francis Online.
A two-group analysis has been applied to the transient behavior of the thermal flux in a subcritical assembly which has been given a short burst of fast neutrons. This analysis has been applied to graphite-U235 reactors having moderator-to-fuel (C/U) atomic ratios of 600, 1200, 2340, and 9550. The results are shown to be in agreement with measurements of the decay of thermal neutrons when short pulses of fast neutrons are incident on assemblies having these C/U ratios.
