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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
Shawky F. Nassar and Glenn Murphy
Nuclear Science and Engineering | Volume 35 | Number 1 | January 1969 | Pages 70-79
Technical Paper | doi.org/10.13182/NSE69-A21114
Articles are hosted by Taylor and Francis Online.
The diffusion parameters of light water have been measured by the pulsed-source method. The neutron bursts were produced from a Texas Neutron Generator by pulsing the ion source and using the 3H (d, n) 4He reaction. Neutrons were injected into spherical volumes of H2O and the decay constants of the neutrons were determined by means of an enriched BF3 miniature proportional counter. Neutron lifetime measurements were performed on small and large water samples with values of the geometric buckling from 0.035 to 0.655 cm−2. A harmonic analysis was conducted for the large geometries, while the waiting time method was used for the smaller ones. In the harmonic analysis, it appeared that a detector in a sphere is more sensitive to neutron fluctuation with time than it would be in a rectangular or cylindrical system. The diffusion parameters, D0 and C, were determined by fitting the decay constants to the equations and , where and are the geometric and the corresponding transport buckling, respectively. The second fit gave a lower standard deviation of C than did the first fit.