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
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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.”
John C. Vigil
Nuclear Science and Engineering | Volume 29 | Number 3 | September 1967 | Pages 392-401
Technical Paper | doi.org/10.13182/NSE29-03-392
Articles are hosted by Taylor and Francis Online.
A method based on analytic continuation, which is well suited for fast digital computer application, has been applied to the point reactor kinetics equations. The most important characteristic of the method is that it yields an analytic criterion for the magnitude of the time step. This criterion is such that the time step automatically expands or contracts, depending on the behavior of the function within each interval. The use of this criterion to determine the time step guarantees that the fractional error in the results increases, at most, linearly with the number of time steps. Furthermore, the magnitude of the time step determined from this criterion can be much larger than the prompt-neutron generation time. Approximate solutions by this method were compared with some analytic solutions to the reactor kinetics equations, and the error accumulation was found, in all cases, to be within the limits predicted by the theory. Comparisons were also made with experimental transients in the Godiva and SPERT I reactors. The approximate results were found to agree well with experiment in the range of reactivity inputs where the feedback model used is valid. In a comparison with another numerical method (RTS code), analytic continuation was found to be 25 times faster.