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
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Byoung Kyu Jeon, Cheol Ho Pyeon, Hyung Jin Shim
Nuclear Technology | Volume 191 | Number 2 | August 2015 | Pages 174-184
Technical Paper | Fission Reactors | doi.org/10.13182/NT14-83
Articles are hosted by Taylor and Francis Online.
Experiments on the isothermal temperature reactivity coefficient (ITRC) have been carried out at the light water–moderated core with or without a D2O tank in the Kyoto University Critical Assembly. The ITRC experiments are analyzed by a continuous-energy Monte Carlo (MC) neutron transport analysis code, McCARD. Through the temperature changes of H2O and D2O, effects of the coolant density changes in moderator and reflector regions and the microscopic cross-section variations on the ITRC are investigated by sensitivity analyses with the use of the MC adjoint-weighted perturbation method. An adjoint-weighted correlated sampling method for the stochastic mixing technique of cross-section libraries is devised to estimate the reactivity change from a perturbation of the thermal scattering cross sections due to the temperature change. From results of the MC perturbation analyses, it is clearly seen that the ITRCs of the two core configurations are dominated by a negative contribution of the number density change of hydrogen in the moderator region and a positive contribution of the thermal scattering cross-section change of hydrogen in the reflector region.