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
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Mar 2025
Jul 2024
Latest Journal Issues
Nuclear Science and Engineering
March 2025
Nuclear Technology
Fusion Science and Technology
February 2025
Latest News
Prepare for the 2025 Nuclear PE Exam with ANS guides
The next opportunity to earn professional engineer (PE) licensure in nuclear engineering is this fall, and now is the time to sign up and begin studying with the help of materials like the online module program offered by the American Nuclear Society.
Walter H. D'Ardenne, Henry E. Bliss, David D. Lanning, Irving Kaplan and Theos J. Thompson
Nuclear Science and Engineering | Volume 32 | Number 3 | June 1968 | Pages 283-291
Technical Paper | doi.org/10.13182/NSE68-A20210
Articles are hosted by Taylor and Francis Online.
Reactor physics parameters were measured in three heavy water lattices consisting of 0.250-in.-diam, 1.03 wt% 235U metal fuel rods in triangular arrays spaced at 1.25, 1.75, and 2.50 in. The following quantities were measured in each lattice: the ratio of epicadmium to subcadmium radiative captures in 238U (ρ28); the ratio of epicadmium to subcadmium fissions in 235U (δ25); the ratio of radiative captures in 238U to fissions in 235U (C); and the fissions in 238U to fissions in 235U (δ28). These experimental results were used to calculate the following reactor physics parameters for each lattice: the resonance escape probability p, the fast fission factor ϵ, the multiplication factor for an infinite system k∞, and the initial conversion ratio C. Analytical results obtained by using THERMOS and GAM-I are in fair agreement with the experimental results.