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
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
Vijay R. Nargundkar, Tejen Kumar Basu, Om Prakash Joneja
Fusion Science and Technology | Volume 12 | Number 3 | November 1987 | Pages 380-394
Technical Paper | Blanket Engineering | doi.org/10.13182/FST87-A25070
Articles are hosted by Taylor and Francis Online.
Neutron multiplication measurements for 14-MeV neutrons were carried out in thick beryllium and graphite assemblies at the Institute for Reactor Development, Jülich, Federal Republic of Germany. Earlier Monte Carlo calculations using the ENDF/B-III library contained systematic errors that did not account for the predominant axial thermalization and non-1/v absorption in polyethylene. In addition, the calculational geometry differed considerably from the experimental geometry. These deficiencies have been eliminated in the present calculations, where the Los Alamos 30-group CLAW-IV library has been used. The anisotropy of the source in space and energy has also been taken into account. The results show that the calculated value of neutron multiplication is 20% higher (originally reported 30% higher) than the measured multiplication in beryllium. The results confirm the measurements made with BeO. For graphite and lead, excellent agreement is found between calculated and measured multiplication.
