ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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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!
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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.”
W. N. McElroy, S. Berg, T. B. Crockett, R. J. Tuttle
Nuclear Science and Engineering | Volume 36 | Number 1 | April 1969 | Pages 15-27
Technical Paper | doi.org/10.13182/NSE69-A18853
Articles are hosted by Taylor and Francis Online.
A multiple foil activation iterative method has been used to experimentally determine neutron flux spectra in various types of neutron environments. The method involves irradiation of a set of different foil detectors, measurement of resultant activities, and adjustment of a spectrum selected as an initial approximation to obtain a good-fit solution for a set of simultaneous activation integral equations. A computer code, SAND-II, is used to obtain this solution. Spectra from thermal and fast reactors and from beam sources have been measured. In each experiment, a set of more than ten foil detectors, encompassing low- and high-energy neutron-induced reactions, was irradiated and used as input to SAND-II. Solutions obtained are compared with diffusion, transport, or Monte Carlo calculations or with spectrometer measurements. It is concluded that the multiple foil activation iterative method is an important adjunct to calculational and neutron spectrometer techniques used to determine neutron flux spectra.