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
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
Fusion Science and Technology
July 2025
Latest News
Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
Morton R. Fleishman, Harry Soodak
Nuclear Science and Engineering | Volume 7 | Number 3 | March 1960 | Pages 217-227
Technical Paper | doi.org/10.13182/NSE60-A25705
Articles are hosted by Taylor and Francis Online.
The Spinrad three-group theory of the fast effect is formulated. Recipes are presented for determining the necessary cross sections directly from fundamental data and three-group cross sections for various materials are tabulated. A comparison is made between the three-group theory and one-group theory with respect to the calculation of R, the ratio of fast-to-thermal fissions, and it is found that the three-group theory appears to give better agreement with experiments. The three-group values of Є — 1 are about 20% higher than those calculated from the one-group formula.
